1,720,960 research outputs found
Energy-assisted forming: theory and applications
Many advanced high strength metals developed for automotive and aerospace applications exhibit poor formability at room temperature. This has led to the development of high temperature processes such as warm forming and hot forming that are expensive in terms of cost and time. It is possible to utilize the viscoplastic nature of the material to enhance the room temperature formability. The use of servo press, ultrasonic-assisted forming, and electrical-assisted forming are few such representative processes. This chapter will explore the fundamentals that govern these processes and also describe the application with case studies from literature. Since all the processes are based on similar principles, the mechanical behavior during processing can be modeled under a common framework. In this chapter, a dislocation density model is proposed as a common model for energy-assisted forming processes
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
“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
We 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
We 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
We 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
Friction welding: An effective joining process for hybrid additive manufacturing
Hybrid additive manufacturing combining bulk components from traditional manufacturing route can overcome the size limitation in typical metal additive process. Investigating the joining process of bulk and additive components is crucial in hybrid processes. In the present work, a comprehensive study, including both experiments and simulations, has been carried out to describe the linear friction welding of electron beam melted Ti6Al4V. Three different welding configuration have been considered: conventional-conventional, EBMelted to EBMelted and the dissimilar conventional-EBMelted. Successive weld joints were achieved in all the three configurations. The mechanical behavior and the phase transformation in the weld region is highly influenced by the base material microstructure. The thermo mechanical behaviour during the friction welding is simulated using finite element method. The temperature history is predicted with very good accuracy in all the three configurations. The experimental data along with the simulation results are used to further explain and understand the phenomena occurring during the welding
Rigorous analysis and pragmatic guidelines in estimating strain rate sensitivity using stress relaxation test
The exponent in power law relation between stress and strain rate during uniaxial deformation is known as strain rate sensitivity, . The parameter provides valuable insights on the underlying rate dependent mechanical behavior. Although can be estimated using macroscopic transient tests like strain rate jump test and stress relaxation test, the kinetics of the dislocation motion and its influence on the is not well documented, resulting in ambiguity of the values estimated from different test procedures. In the present work, it is shown that the value estimated from stress relaxation test is not accurate owing to the transient nature of dislocation density during relaxation. A new methodology is demonstrated to accurately estimate from stress relaxation test. The methodology is demonstrated using four different aging conditions of a commercially available AA 7075 alloy. A simplified closed form analytical equation is proposed for the ratio of strain rate sensitivities obtained from the traditional and new procedure
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