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    Microstructural and mechanical properties of welded SSM356-T6 and SSM7075-T6 aluminum semi-solid sheets by friction stir welding

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    Friction Stir Welding (FSW) was the welding process applied in this research to join different grades of aluminum alloy sheets Semi-Solid Metal (SSM) 356-T6 and 7075-T6. The test pieces have dimensions of 50 mm × 100 mm × 4 mm. The effect of tool rotational speed on metallurgy, and mechanical properties of welding was investigated. Dissimilar butt joints were produced by using cylindrical pin with conditions of different tool rotation speed (710, 1,000 and 1,400 rpm) and welding speed (80, 112 and 160 mm/min). The welding microstructures showed three different areas including base metal, stir zone and thermo mechanical affected zone, which were directly affected by the rotation speed of tool. The butt joint rotation speeds 1,000 rpm provided the average maximum tensile strength 246.33 MPa. Rotational speed allowed material flow from the from to the rear of the tool. The heat generated from friction lead to microstructural change and promote good mix and adhesion of both materials

    Development of Mixing and Pressing Processes of Split-Gill Mushroom Spawn Blocks

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    This study aims to develop the mixing and pressing processes of split-gill mushroom spawn blocks through the development and construction of a semi-automatic mushroom spawn mixing. The developed machine uses a 0.5 hp motor to drive the mixing tank and the press cylinder, which are connected to a 1:60 reduction gear. The results show that the semi-automatic mushroom spawns mixing and pressing machine developed in this study are within the standard ranges, that the split-gill mushroom spawn blocks with an average weight of 598 g, an average height of 10.2 cm, and an average density of 0.33 g/cm3. As for production capacity, manual pressing produced 40 mushroom spawn blocks per hour while the developed machine produced 112 mushroom spawn blocks per hour, which is 2.8 times faster

    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

    An Investigation of the Optimal Cutting Conditions in Coconut Wood and Palmyra Palm Wood Turning Process Using Design of Experiment

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    The purpose of this research is to investigate the effect of factors on the surface roughness in the coconut wood and palmyra palm wood turning process for manufacturing furniture parts using carbide cutting tools. The main factors, namely, cutting speed, feed rate and depth of cut were investigated for the optimum surface roughness in furniture manufacturing process. Normally, an acceptable surface roughness is between 3.0 - 9.0 µm before the sanding process. The result of preliminary trial shows that the depth of cut had no effect on surface roughness. Moreover, it was found from the experiment that the factors affecting surface roughness were cutting speed and feed rate, with a tendency for reduction of roughness value at lower feed rate and greater cutting speed. Therefore, in the turning process of coconut wood, it was possible to determine a cutting condition by means of the equation Ra = 3.90 - 0.00375 Cutting Speed+7.93 Feed Rate, This equation can be best used with a limitation of cutting speed at 170 - 353 m/min, feed rate at 0.05 - 0.16 mm/rev and depth of cut at 1 mm. In the turning process of palmyra palm wood, equation Ra = 3.38 - 0.00164 Cutting Speed+10.8 Feed Rate, This equation can be best used with a limitation of cutting speed at 188 - 392 m/min, feed rate at 0.05 - 0.12 mm/rev and maximum depth of cut at 1 mm. To confirm the experiment result, a comparison between the equation value and an actual value by estimating a prediction error value was calculated with the surface roughness and margin of error not over 10 %. The result from the experiment of mean absolute percentage error of the equation of surface roughness is 4.28 % for coconut wood and 3.47 % for palmyra palm wood, which is less than the predicted error value and is acceptable

    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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