1,720,971 research outputs found
Design, development and test of a novel broach for long polypropylene tubes
No full textPolymers are frequently used for a variety of applications in industry. One relevant field is plastic tubing. As plastic tubes are manufactured from thermoplastic material through hot-extrusion their dimensional accuracy is only moderate. Wherever high accuracy on tube diameters and roundness are required, the conventional production techniques reach their limits and more complex technologies are needed. Known approaches from metal machining are deep hole drilling and internal broaching. However, machining processes with chip removal on polymeric materials are not so common. Therefore, the authors studied cutting operations of polypropylene experimentally. Based on their findings they designed and built an internal broach for the machining of polypropylene tubes. Finally, the authors tested their developed broaching tool in a relevant industrial environment. The tool not only fulfills the dimensional machining requirements but also solves the present chip evacuation problem in a unique way. It enables free cutting through the whole operation and creates continuous straight chips with no need for chip breakers. Consequently, the timely cleaning step, required in traditional broaching, can be eliminated, which reduces the lead time significantly. Furthermore, the set of materials allows dry broaching. Coolant is not necessary. This leads to less waste, a cleaner production line, and avoids damage through aggressive liquids. Lastly, their design ensures that no loss of dimension occurs when resharpening the tool
Fast development cycle for the design of industrial grippers
No full textRecent trends, such as Supply Chain agility, just in time delivery, and mass customization of products, are pushing automated production processes in Industry 4.0 towards increasing flexibility. Although the entire set of devices is already on the market and can be selected according to the needs, the element that regularly has to be redesigned is the robotic end effector, mainly a gripper. Therefore, we established a Fast Development Cycle to accelerate the design and test process of new industrial grasping devices. The cycle consists of the three main steps: Build, Test, and Learn. The most fundamental aspect of the methodology is to decompose a gripper idea into its essential uncoupled constituents and convert it into a gripper pretotype that is solely oriented to validate its basic principles. This procedure ensures a quick initial building phase and allows to enter testing early. Test results are used to evaluate the initial idea, to enhance knowledge and to create the input for the next turn of the cycle. During each turn the design evolves further while reducing uncertainties. Contrary to traditional product development, this method enables to test the feasibility of a device in the earliest possible stage with the least possible amount of time and money. The single steps of the methodology are illustrated in this paper in detail based on real cases from industry. The successful development of industrial grippers from these real cases through the Fast Development Cycle demonstrates its applicability. Instead of optimizing complex systems, the methodology generates simple solutions with a high potential for cost savings in the design and production process of the devices themselves and during their operation in automated production processes in several industries. The methodology applies regardless of the underlying physical principles and encounters the use of TRLs as KPIs to measure technology maturity
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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