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Parallel DEM Simulation Strategy
No full text有鑑於離散元素法的模擬隨元素數量增加伴隨而來的龐大計算時間，本研究提出了離散元素法的平行策略，而此平行策略係建立在一個能勝任多種元素形狀與多種元素間力學機制的離散元素模擬的離散元素程式架構，名為VEDO架構(VErsatile Discrete Objects framework)，其設計上將元素模型描述與力學機制演算法兩者抽離，僅在執行期間求解碰撞力學行為時將兩者作動態連結。本研究詳述了平行策略中的各項細節，包括工作量如何分配、處理器間溝通的時機與訊息內容等。
本研究建置出的平行離散元素模擬程式已應用在自充填混凝土砂漿的流動行為模擬。砂漿元素為由混凝土中細骨材、水、粉體共同構成的膠狀溶液，欲作自充填混凝土的流動模擬，可取其離散元素模型為粗骨材元素(代表粗骨材)與砂漿元素的二相組合。然而，砂漿元素為以離散顆粒模擬漿液的虛擬元素，顆粒參數與配比參數的關聯必須先經由砂漿流動試驗數據與砂漿流動模擬結果來建立。由於三維砂漿模擬需要很多的元素數目以致於計算量龐大，本研究建置出的平行離散元素程式藉由多個處理器的分工以減少執行時間，以使三維砂漿模擬能實現。In order to reduce the computation time involved with DEM (Discrete Element Method) simulation with large numer of elements, this research proposes a parallel strategy for a DEM simulation program framework, named VEDO (VErsatile Discrete Objects framework). In the design of VEDO framework, element model description and inter-element mechanism algorithm are separated, so VEDO framework is capable of performing simulations having elements with various shapes and various inter-element mechanisms. The complete detail of the proposed parallel strategy, including how to distribute the work-load, when and by what content will the collaborating processors communicate, is presented in this thesis.
For conducting a flow simulation of Self-Compacting Concrete (SCC) using DEM, the element model can be a two-phase combination of arrgegate and mortar particles. The former simulates the real-world coarse aggregates, and the latter simulates the mortar solution composed of fine aggregates, water and cement. Because the mortar particles are “virtual” in the sense that they do not correspond directly to discrete mortar objects in the real world, the relationships between mechanical parameters of the mortar particles and mix proportion must be established in advance from both the results of mortar flow simulation and mortar flow tests. However, mortar flow simulations require huge computation time. Therefore, a parallel DEM program has also been developed in this research to make feasible the three-dimensional flow simulation of motar solution.致謝 i
摘要 iii
Abstract v
目錄 vii
圖目錄 ix
表目錄 xiii
第1章 緒論 1
1-1 研究背景與目的 1
1-2 研究方法與步驟 7
1-3 論文組織 9
第2章 模擬工具 11
2-1 VEDO架構的優點 11
2-2 傳統離散元素法程式實作 13
2-3 VEDO架構核心類別的設計 18
2-4 VEDO架構輔助類別的設計 20
2-5 Knight&Anne 25
第3章 平行策略 27
3-1 傳統離散元素程式的平行策略 27
3-1-1 Atom Decomposition 28
3-1-2 Force Decomposition 30
3-1-3 Spatial Decomposition 32
3-2 本研究的平行策略 33
3-2-1 辨認所需的Interaction物件 36
3-2-2 處理器間交換元素作用力局部總合 40
3-2-3 同步化各元素資訊 42
3-2-4 分配Interaction物件 43
3-3 VEDO架構的擴充 54
3-4 平行效率評估 58
第4章 案例研究 75
4-1 自充填混凝土流動性質 76
4-2 砂漿流動性質的模擬方法 80
4-3 砂漿流動模擬 90
第5章 結論與建議 95
5-1 結論 95
5-2 建議 96
參考文獻 98
作者簡歷 10
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
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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