1,720,984 research outputs found

    Modeling of cutting force in micro-end-milling process with experimental validation on additive manufactured Nickel-based superalloy

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    Nowadays aerospace, microelectronics, biotechnology industries require small sized components with complex shape and high mechanical properties, often operating in aggressive environment. In this framework, Additive Manufacturing (AM) of Nickel-based superalloys is an interesting and cost effective process. Fewer design constraints and the weight reduction achievable through the topology optimization are the most relevant AM advantages. Furthermore, micro-scale features on the additively fabricated parts can be manufactured by using micro machining. Subtractive processes ensure to achieve high-precision mechanical coupling due to better surface finishes and tighter tolerances. A lack of scientific studies focusses on the material removal behavior of difficulty-to-cut alloys produced via Additive Manufacturing is evident. This work describes a machining analytical force models which considers the presence of ploughing- and shearing- dominated cutting regimes. The undefined cutting force model parameters and the Minimum Uncut Chip Thickness (MUCT) can be identified through proper experimental tests. The refinement procedure of the model was utilized to characterize Inconel 625 samples fabricated by LaserCUSINGTM. The cutting force data were elaborated with an iterative methodology based on a search algorithm. The model successfully predicted how the cutting force changes as a function of the process parameters

    Analytical force modelling for micro milling additively fabricated Inconel 625

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    In recent years, miniaturization of components has been concerned with several industrial fields including aerospace, energy, and electronics. This phenomenon resulted in increasing demand of micro-components with complex shape and high strength, often in high-temperature environment. Nickel-based superalloys such as Inconel 625 are a class of material suitable to aforementioned applications and can be successfully processed with Additive Manufacturing (AM). Moreover, micro-milling can be employed to manufacture micro-scale features on the additively fabricated parts or to achieve better surface finishes, as required for high-precision mechanical assemblies. In micro machining, it is possible to notice a lack of scientific study focusses on the material removal behavior of difficulty-to-cut alloys produced via Additive Manufacturing. This paper describes an analytical cutting force model suitable also for AM’d parts which considers the presence of ploughing- and shearing- dominated cutting regimes. A refinement procedure of the cutting force model was defined and applied by performing an experimental work on Inconel 625 samples fabricated by LaserCUSINGTM. A search algorithm was employed to develop an iterative methodology to determine the unknown cutting force model parameters. The model was successfully utilized to predict how the cutting force is affected as the process parameters change

    Machining Applications

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    There has been an increasing demand for biomedical devices including various instruments, apparatuses, implants, in vitro reagents, and similar articles to diagnose, prevent, or treat diseases, improve human health, prolong human life, and recover from serious injuries. Biomedical devices that we utilize are not only continuously getting smaller and more effective but are also designed with more customized functionalities. In response to that demand, new design innovations, new materials, and prototypes of novel medical devices have been introduced on a regular basis. Design, prototyping, and manufacturing techniques for these materials and designs have also been continuously developing in parallel to the needs in biomedical device demands. There have been a large number of books written about design and manufacturing of various products but biomedical device manufacturing remains less covered than other well-known microelectronics and consumer products. This book brings authors from institutions around the world, perhaps one of the few wide-ranging books on manufacturing processes for medical devices with coverage of various materials including metals and polymers. The book aims to reach audiences such as practicing engineers who are working in medical device industry, students in the biomedical device manufacturing courses, and faculty/researcherswho are conducting research in medical device design, prototyping, and manufacturing

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    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

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    “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

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    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

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    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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    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
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