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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
압력 구배 흐름에서의 고농도 알루미나 현탁액의 복잡 거동
Get PDF학위논문 (박사)-- 서울대학교 대학원 : 화학생물공학부, 2013. 8. 안경현.A new approach was taken to understand the flow behavior of concentrated particle suspensions in pressure-driven capillary flow. The flow of concentrated alumina suspensions in a slit channel was visualized depending on dispersion states, coagulated system and well-dispersed system, with modified capillary rheometer. The complex flow behaviors of suspensions including the flow development in solid-liquid transition process were quantitatively described in terms of flow profile and pressure fluctuation.
The suspensions showed complex flow behaviorsunique solid-liquid transition and shear banding. In the solid-liquid transition, there was no-flow at first and continuous change of flow profile was observed with time. At low shear rates in particular, the suspensions exhibited shear banded flow profile which could be divided into 3 regions: the region with low flow rate near the wall, the region with rapid increase of flow velocity to maximum, and the region of velocity plateau. The banding in pressure-driven flow was different from that in Couette flow. The banding of concentrated alumina suspensions was unique in that sluggish velocity profile was pronounced and two inflection points in velocity profile was exhibited. Based on both flow visualization and measurement of shear stress, it was found that the shear banded flow profile in pressure driven slit channel flow was strongly correlated with shear stress.
For the coagulated alumina suspension, the shear stress showed an N-curve that included a region of stress decrease with an increase in shear rate followed by a monotonic increase. Depending on the region in the stress curve, the flow profile changed from a shear banded profile with no-flow or sluggish flow rate closed to the channel wall and plug flow at channel center to a plug-like flow profile similar to the Newtonian fluid. In addition, it was observed that the transient flow behavior over time at high shear rate in liquid state experienced all of the steady state flow profiles at lower shear rates in solid-liquid transition. During the solid-liquid transition, the flow profile was found to be shear banded, and the pressure profile did not reach a steady state but fluctuated with a characteristic time period. As the solid concentration increased for the coagulated system, the flow profile in the solid-liquid transition region (stress-decay region) exhibited more complex flow behavior of very large no-flow region along with an asymmetric flow and its fluctuations. With the FT analysis of pressure fluctuation and flow fluctuation, it was determined that pressure fluctuation had the same time period with the flow profile fluctuation and the flow profile change in the slit channel had close relationship with the pressure change, which is meaning of that the pressure fluctuation is caused by the complex flow behavior inside the channel.
In contrast with coagulated suspension, the well-dispersed suspension with low solid concentration showed only a monotonic increase of shear stress in the range of shear rates we could measure, indicating that the suspension was in liquid state. The flow profile was plug-like, and the pressure was fluctuating without any characteristic time period. However, the well-dispersed suspensions with higher solid concentration exhibited complex flow behaviors similar to coagulated suspension such as unique solid-liquid transition and shear banded flow profile.
In this study, shear banding of concentrated alumina suspensions in slit channel flow was visualized and quantitatively analyzed. We expect this approach can be an effective method to understand the flow behavior of particulate suspensions in the pressure-driven flow which is typical in industrial processing.Abstract ........................................................................................ i
List of Figures ...........................................................................................vii
1. Introduction .............................................................................1
1.1. General introduction .............................................................................2
1.2 Outline of the Thesis ..............................................................................6
2. Background ..............................................................................8
2.1. Colloidal particle interaction ................................................................8
2.1.1. Introduction ....................................................................................8
2.1.2. Inter-particle interaction force ........................................................8
2.1.2.1. van der Waals attraction force ..................................................9
2.1.2.2. Electro-static force .................................................................10
2.2. Shear banding of concentrated suspension .........................................16
2.2.1. Shear banding ...............................................................................16
2.2.2. Plateau in flow curve or stress plateau .........................................16
2.2.3. Velocity profile of shear banding in simple shear flow ................18
3. Experimental methods ..........................................................21
3.1. Sample preparation .............................................................................22
3.2. Experimental set-up ............................................................................27
3.2.1. Modification of conventional capillary rheometer .......................27
3.2.2. Flow visualization using modified capillary rheometer ...............29
3.2.3. Data analysis method for pressure fluctuation .............................33
4. Results and Discussion ..........................................................38
4.1. Verifying the performance of modified capillary rheometer ..............39
4.1.1. Verification of rheological properties ...........................................39
4.1.2. Verification of flow visualization .................................................42
4.2. Flow visualization of well-dispersed alumina suspensions ................44
4.2.1. Transient flow behavior ................................................................44
4.2.2. Steady state flow behavior ...........................................................47
4.2.3. Correlation between flow behavior and shear stress behavior .....54
4.3. Flow visualization of coagulated alumina suspension .......................60
4.3.1. Steady state flow behavior ...........................................................60
4.3.2. Correlation between flow behavior and shear stress behavior .....62
4.3.3. Flow development and solid-liquid transition ..............................65
4.3.3.1. Transient flow behavior .........................................................65
4.4.3.2. Flow development in solid-liquid transition ..........................67
4.3.4. Time periodic pressure fluctuation of coagulated alumina suspension in solid-liquid transition ......................................................70
4.4. Flow instability of coagulated alumina suspension with high solid concentration .............................................................................................74
4.4.1. Flow instability in slit channel flow .............................................74
4.4.2. Pressure fluctuation and its relation to flow instability ................89
5. Conclusion ..............................................................................98
Reference ..................................................................................102
국문초록....................................................................................113Docto
Variations on the Author
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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