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Electrical Control of Liquids at Interfaces: Electrowetting, Dielectrowetting, and Dewetting
No full text近十年來，液體介面的電操控已廣泛運用在微流體元件的應用上。然而，液體於元件內之動態運動行為無法從實驗中清楚解析。因此，我們開發一個考慮弱介電質模型的電流體力學理論與相場法之間耦合的數值模擬方法來求解液體介面受到外加電場影響後隨時間變形的課題。透過此弱介電質模型的假設，我們提出的數值模擬模型可以模擬無論以導電液體或介電液體為操控目標的微流體原件。 我們針對電濕潤顯示器畫素內導電液體與介電液體之介面的動態運動行為進行討論。我們所發展的數值模型成功模擬了畫素開啟時的反濕潤與電濕潤現象及畫素關閉時的流體攤平現象。考慮液體接觸角隨電壓的變化於模型中，電壓與開口率的模擬結果與相關的實驗測試相當吻合。此外，我們亦藉由數值模擬模型的參數分析探討了電濕潤顯示器在驅動過程中所發生的油墨分裂、油墨跳墨以及油墨平鋪不均等元件缺陷的現象。釐清元件缺陷的原因後，我們成功開發了一個高穩定的電濕潤顯示器。 此篇論文亦由宏觀與微觀的層面討論了介電液體與空氣間介面受到外加電場影響所產生的介電濕潤現象。我們藉由實驗與數值模型探討了液體表面的皺褶行為、電極形狀與液滴大小對液體等向流動之課題，以及液體在電壓釋放後之反濕潤現象。這些結果提供了許多與介電濕潤理論相關的資訊於介電濕潤光閘元件的開發上。 過去已提出的液體介面電操控的方式僅能製作出週期性之形狀(對稱波)或球狀結構(僅有兩個主曲率半徑)。在此研究中，我們開發了兩種能夠建構更複雜流體介面形狀的電操控方法。第一種電操控方式是藉由電容值感應的回饋控制使得每個控制電極上方之流體厚度能夠被準確掌控；而第二種電操控方式是透過電極產生多個週期性的輸出波形導致流體以傅立葉組合的形式建構出複雜的形狀。過去在電濕潤應用所使用的材料可以直接運用於此開發元件上。此外，因為流體在操控時的反應速度足夠慢(毫秒-微秒)，使得傳統的電子控制元件(微秒-奈秒)足夠匹配。最後，由於此元件中的導電液體不會碰觸電極上方的固態表面，因此介電材料的特性退化議題可以被忽略。Electrically based control of the geometry or transport of a fluid meniscus has been a technological trend used in microfluidic applications in the last decade. Aside from experiments, numerical models could provide an effective tool for testing the feasibility of device applications. Here, we present a numerical simulation technique to calculate the deformation of fluids at interfaces by coupling the electrohydrodynamic (EHD) theory considering the assumption of leaky dielectric model with the Phase Field Method (PFM). With the assumption, the proposed model could simulate the interaction of a fluid-fluid interface with an electric field, using conductive liquids as well as dielectric liquids. The fluid dynamic behavior within a pixel of an electrowetting display (EWD) is studied. The complete switch processes, including the break-up and the electrowetting stages in the switch-on process (with voltage) and the oil spreading in the switch-off process (without voltage), are successfully simulated. By considering the factor of the change in the apparent contact angle at the contact line, the electro-optic performance obtained from the simulation is found to agree well with its corresponding experiment. In addition, the proposed modeling is used to parametrically predict the effect of interfacial (e.g., contact angle of grid) and geometric (e.g., oil thickness and pixel size) properties on the defects of an EWD, such as oil dewetting patterns, oil overflow, and oil non-recovery. With the help of the defect analysis, a highly stable EWD is both experimentally realized and numerically analyzed. Dielectrowetting effects of surface wrinkling, droplet size, isotropic vs. anisotropic spreading, electrode geometry, and deterministic dewetting, are presented both experimentally and by the developed model. The dynamic behavior of the two phase system has been accurately characterized on both the macro and microscopic level. These results can be used to further optimize dielectrowetting optical shutter and to provide a deeper theoretical insight into the operating physics of dielectrowetting effect. Existing techniques for electronic control of the interface between two immiscible fluids are typically limited to simple periodic geometries (symmetric waves) or spherical geometries (only two principle radii of curvature). Presented here, is a new technique with much more sophisticated electronic control of fluid meniscus geometry. Two distinct approaches are demonstrated: (1) application of voltages, electrical capacitance sensing of meniscus geometry, followed by further feedback control of the applied voltages based on the sensed electrical capacitance; (2) use of multiple periodic voltage waveforms and wave propagation across the meniscus to build up complex meniscus geometries by Fourier construction. The results can be achieved using conventional materials, and the fluids respond with speeds that are adequately slow (ms-µs) such that even conventional control electronics (µs-ns) are more than adequate. Furthermore, because the conducting fluid never dewets the oil film from the solid surface, dielectric degradation issues are likely eliminated
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
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
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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