1,721,210 research outputs found
sj-docx-1-ist-10.1177_03019233241242252 - Supplemental material for Modulation of δ-ferrite formation and austenite stability in Al-added medium-Mn steels and its role in the structure–property relationships
No full textSupplemental material, sj-docx-1-ist-10.1177_03019233241242252 for Modulation of δ-ferrite formation and austenite stability in Al-added medium-Mn steels and its role in the
structure–property relationships by Deepak Kumar, Mukesh Kumar Yadav, Navanit Kumar, Indrani Sen and Tapas Kumar Bandyopadhyay in Ironmaking & Steelmaking</p
sj-docx-2-pic-10.1177_09544062231207058 – Supplemental material for Dynamic performance of newly developed environmentally friendly greases containing polysaccharide gums in rolling bearing
No full textSupplemental material, sj-docx-2-pic-10.1177_09544062231207058 for Dynamic performance of newly developed environmentally friendly greases containing polysaccharide gums in rolling bearing by Ankit Saxena, Deepak Kumar and Naresh Tandon in Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science</p
sj-docx-1-pic-10.1177_09544062231207058 – Supplemental material for Dynamic performance of newly developed environmentally friendly greases containing polysaccharide gums in rolling bearing
No full textSupplemental material, sj-docx-1-pic-10.1177_09544062231207058 for Dynamic performance of newly developed environmentally friendly greases containing polysaccharide gums in rolling bearing by Ankit Saxena, Deepak Kumar and Naresh Tandon in Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science</p
Supplemental Material - Quantifying the Systematic Bias in the Accessibility and Inaccessibility of Web Scraping Content From URL-Logged Web-Browsing Digital Trace Data
No full textSupplemental Material for Quantifying the Systematic Bias in the Accessibility and Inaccessibility of Web Scraping Content From URL-Logged Web-Browsing Digital Trace Data by Ross Dahlke, Deepak Kumar, Zakir Durumeric, and Jeffrey T. Hancock in Social Science Computer Review</p
A novel sink-hole fluidization method for dry separation of 1-10 mm particles at cut points above 2500 kg/m³
No full textIncreasing water restrictions make it desirable to increase the use of dry processes in mineral beneficiation. Air dense medium fluidized beds (ADMFBs) are one of the most effective methods of dry separation, especially for fine coal and minerals applications. However, dry processes usually struggle to separate particles as efficiently as wet processes, especially for particles finer than about 10 mm. This research was concerned with the separation of 1-10 mm particles of density between 2.4 and 4.8 RD. Experiments were conducted in two phases. The Phase 1 device consisted of a 1 mm mesh screen above a 200 mm diameter dense medium fluidized bed, mounted on top of a Kason vibratory device with the help of struts. The screen mesh above the fluidized bed contained a centrally located opening, which was large compared to its 1 mm aperture, referred to as a “Sink-Hole”. The experiments in this phase were performed using 2.0-2.8 and 2.8-4.0 mm tracer particles using nominal 200 μm volume median diameter sand or a 85:15 mix of sand with hematite as the fluidized medium with a single centrally located 13 mm diameter Sink-Hole. The performance of the system was monitored to separate the particles based on their density. However, there were reproducibility issues with the Phase 1 system which lead to changes being made. The Phase 2 device consisted of a pair of 1 mm aperture screens above a 200 mm diameter dense medium bed. These were directly mounted on top of the same Kason vibratory device as in Phase 1, but this time it was set in a different vibration mode that better assisted the transport of the particles across the Sink-Hole. The screen on top contained a centrally located Sink-Hole. The secondary screen mounted 15 mm below the top screen improved the bed homogeneity by suppressing the bubbles within the fluidized bed, and also enabled the underflow particles to be more easily captured and counted. Again, the experiments in Phase 2 started with a 13 mm diameter Sink-Hole. However, during Phase 2 experiments, the diameter of the Sink-Hole was also varied from 13 to 60 mm. Most of the experiments were again performed using the sand of nominal median size 200 μm, skeletal density 2643 kg/m³ and Umf of 2.5 cm/s. Tracer particles ranging from 2.0 to 8.0 mm in size and 2400 to 4800 kg/m³ in density were used to measure the partition performance. Different operating conditions were explored. The optimum (lowest Ep) operating conditions were found to be at superficial velocities of 2.5-3.0 times the minimum fluidization velocity, with the fluidised bed just reaching the level of the Sink-Hole. Sand flowed upwards through the Sink-Hole and then spread out and percolated back through the surrounding mesh. The system was found to reach a dynamic equilibrium separation state, in which sometimes particles that had previously passed through the Sink-Hole would re-emerge onto the upper screen. Robust performance with relatively sharp separations (Ep values below 0.2 RD) was obtained over a wide range of conditions, and results were reproducible within the expected 95 % confidence intervals. Increasing the Sink-Hole size from 13 to 60 mm in diameter improved the separation kinetics, causing the time to reach equilibrium to decrease from about 300 s down to less than 20 s. Either increasing the Sink-Hole diameter or the superficial air velocity under the same operating condition lowered the separation density. Remarkably, the separation densities covering the range 2.5 to 4.0 RD, were higher than the medium density and, invariably higher even than the skeletal density of the medium sand particles. Furthermore, over the range of particle sizes from 2.8 to 8.0 mm, the separation density was fairly insensitive to the particle size, a useful feature for a potential beneficiation device. These features indicate that the separation mechanism at work was very different to the buoyancy mechanisms that determine the separation performance of conventional dense-medium fluidised beds. To further improve the understanding of this intriguing behaviour, a transparent two-dimensional rig was constructed and used to observe the granular flow. A column of upwards flowing material was observed to form beneath the Sink-Hole, extending upwards from a considerable distance below the bed. This observation might explain how particles that had previously sunk through the Sink-Hole could re-emerge at later times. It is speculated that the material in this column was in a critical jammed state part way between that of a packed bed (able to support large loads) and a fluidised state (unable to support loads from particles denser than the bed bulk density). Theoretical modelling using Discrete Element Modelling (DEM) would likely illuminate further this proposed mechanism based on a jamming condition between the particles. Further work is also needed to explore the potential to achieve scaled-up to a commercial-scale continuous device
Novel jamming mechanism for dry separation of particles by density
No full textA novel system involving a gas-solid fluidized bed subjected to vibration was investigated, building upon Kumar et al.(2018). A mesh with an aperture of 1 mm, incorporating a large central hole referred to as a Sink-Hole, was located just below the surface of a fluidized granular media. The fluidized granular media, nominally 0.3 mm sand particles, expanded through the large Sink Hole, spilling onto the top of the mesh, and then sifted back into the lower fluidized zone. The effective density of the medium at the mouth of the Sink Hole was determined by examining the probability of a large tracer particle of a given density floating as opposed to sinking. The effective density was deemed to be the condition denoting a 50 % probability of the tracer particle passing through. Interestingly, this density condition greatly exceeded the density of the medium and invariably the density of the granular media itself. Moreover, the effective density was largely independent of the size of the tracer particles covering the range 2.8 to 8.0 mm, a sign of genuine density-based separation. The underlying mechanism was attributed to a self-organised, tenuous, jamming condition that develops at the mouth of the Sink Hole. As the diameter of the Sink Hole increased, the separation density decreased, while the speed at which the sorting of the test particles occurred increased significantly. A 60 mm diameter Sink-Hole achieved a steady state separation within approximately 10 seconds, and a remarkably sharp density-based separation
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
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