1,720,959 research outputs found
The analytic function expansion nodal method refined with transverse gradient basis functions and interface flux moments
No full textA refinement of the analytic function expansion nodal (AFEN) method is described. By increasing the number of flux expansion terms in the way that the original basic functions are combined with the transverse-direction linear functions, the refined AFEN method can describe the flux shape in the nodes more accurately, since the added flux expansion terms still satisfy the diffusion equation. The additional nodal unknowns introduced are the interface flux moments,, and the additional constraints required are provided by the continuity conditions of the interface flux moments and the interface current moments. Also presented is an algebraically exact method for removing the numerical singularity that can occur in any analytic nodal method when the core contains nearly no-net-leakage nodes. The refined AFEN method was tested on the Organization for Economic Cooperation and Development (OECD)-L336 mixed-oxide benchmark problem in rectangular geometry, and the VVER-440 benchmark problem and a nearly no-net-leakage node embedded core problem, both in hexagonal geometry. The results show that the method improves not only the accuracy in predicting the flux distribution but also the computing time, and that it can replace the corner-point fluxes with the interface flux moments without accuracy degradation, unless the problem consists of strongly dissimilar nodes. The possibility of excluding the corner-point fluxes increases the flexibility in implementing this method into the existing codes that do have the corner-point fluxes scheme and may make it fit better for the nonlinear scheme based on two-node problems
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
Design and characterization of passive recycle-micromixer
No full textA new design was devised for a recycle micromixer, i.e., a passive micromixer with side channels for a recycle flow. The geometry, required to perform a recycle flow and effective mixing, was determined by a simulation based on computational fluid dynamics. A recycle flow of the mixed flow of each unit was introduced to the inlet flow, and a circular flow was generated in the body of the mixer. For complete mixing, five units of the micromixer were connected in series. The simulations were performed at Reynolds numbers of 7, 14 and 28 and channel depths of 100, 150 and 200 μm. Mixing efficiency and direction of recycle flow were significantly affected by both Re and channel depth. When channel depth was 150 μm, mixing efficiency of the micromixer increased from 89.3 to 95.6, 98.4 and 98.6% with the increase of Re from 7 to 14, 28 and 42, respectively. The increasing channel depth also increased mixing efficiency. The micromixer was fabricated by a conventional photolithography technique using polydimethylsiloxane. Color dispersion in blue ink was compared with simulated flow patterns. The characterization of mixing in the recycle micromixer was verified by using an aqueous NaOH solution and phenolphthalein solution, composed of the same volume of ethanol and water. For both cases, fully mixed profiles were achieved along five micromixers, connected in a series at a flow rate of 0.1 ml min−1 for each flow and a short residence time of 0.11 s
In situ thermal diagnotics of the micro-PCR system using liquid crystals
No full textA simple, reliable liquid crystal (LC) thermometry of a polymerase chain reaction (PCR) chip that has a microchamber inside the chip and a film heater and a film sensor patterned on the surface is firstly introduced. The silicon-based PCR chip is made by MEMS technology. A non-linear feedback proportional-integral control scheme adjusts the power input of the Pt heater to control the surface temperature of the micro-PCR chip measured by the Pt sensor with an accuracy of less than ±0.1 °C at steady state. We use the LC thermometry to analyze the temperature distribution in the microchamber of the micro-PCR chip. The reflected colors of LC's inside the microchamber are captured through a charge-coupled device (CCD) camera, subsequently analyzed using a hue-based color analysis system. Two LC's of which individual working range is near the typical PCR temperature of 55 °C and 72 °C are calibrated in a constant temperature bath with a resolution of less than ±0.3 °C. While the average microchamber temperature near the annealing temperature is similar to the surface temperature, it is lower than the surface temperature by ca. 1 °C in the range of the extension temperature. Also, the temperature variations along the center of the microchamber, are less than 1.5 ± 0.5 °C and 3 ± 0.3 °C in the range of the annealing and the extension temperature, respectively
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
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