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Design of a Fuzzy Gain Scheduling of Proportional-Integral Controller for BLDC Motor Applications
No full text無刷直流馬達在轉動電機上的應用越來越廣，然其因有限霍爾元件所造成的變取樣現象與因負載改變造成受控特性的改變，一直沒有最佳的解決方法。本論文詳細探討應用於無刷直流馬達的控制器，以比例-積分控制器為基礎、結合模糊控制理論，提出模糊增益規劃比例-積分控制器，嘗試解決上述兩個問題。獻記載模糊控制器的發展多半以一階輸入速度為主，較高階的處理則會將輸入微分，形成兩個變數，以達成高階模糊控制。此外亦有文獻記載著兩個輸入的二階控制器，如直接轉矩控制，除了回授轉速之外，也將電流予以回授以達成更穩定的轉速響應，相對的也提高了設計控制器的難度。論文提出一模糊增益規劃比例-積分控制器，採用轉速與負載轉矩為輸入，負載則藉由量測定子電流與轉速估測而得，估測方式將在論文中詳述。該控制器具有設計簡單的優點，既無設計高階控制器之困難度又能具有快速的響應。系統的模擬將在論文中詳述，並提供實驗結果加以驗證。Brushless DC Motor (BLDC) Drive has been more and more popular in Electric Motors. However, there is no best solution for the variable sampling caused by limited Hall sensors and the alteration of plane characteristics resulted from the change of load. Control method will be discussed in this thesis. Based on Proportional-Integral（PI） controller and Fuzzy Control theory, a Fuzzy Gain Scheduling Controller is proposed in this thesis.ost of the papers on Fuzzy PI Controller discussed only about one input, and some advanced applications may use the derivation of input to make it become two inputs. Literature also stated that two-order controllers with two inputs, such as Direct Torque Control (DTC), in addition to the feedback of speed, will also send current as a feedback in consideration of achieving a better speed response. However, in doing so, the difficulty of designing the controller will be raised, too. Fuzzy Gain Scheduling PI Controller, monitors the speed and load torque as inputs, is proposed in this thesis. Load torque is estimated by measuring the speed and current of stator, the estimation will be discussed in this thesis. The advantage of Fuzzy Gain Scheduling PI Controller proposed in this thesis is easier to design. Moreover, it could keep the fast speed response. The simulations and experiment results will be given in this thesis.摘要 ibstract ii錄 iii目錄 v目錄 vii一章 緒論 1.1 研究背景 1.2 文獻回顧 1.3 研究目的 2.4 研究貢獻 2.5 章節介紹 2二章 三相六開關直流無刷馬達 4.1前言 4.2直流無刷馬達驅動 4.3三相六開關變頻器切換法則 7.4 小結 11三章 模糊增益規劃比例-積分控制器 12.1前言 12.2 比例-積分控制理論 12.3 模糊增益規劃比例-積分控制器 14.3.1 設計步驟 14.3.2 轉速計算 27.3.3 轉矩估測器 29.4小結 29四章 模擬結果 30.1轉速型模糊增益規劃控制器 30.2轉矩型模糊增益規劃控制器 37.3 模糊增益規劃比例-積分控制器 43.4 小結 58五章 實驗結果及分析 59.1實驗系統架構簡介 59.2 DSP TMS320F2812介紹 61.3濾波器及光耦合隔離 63.4轉速型模糊增益規劃控制器 65.5轉矩型模糊增益規劃控制器 69.6模糊增益規劃比例-積分控制器 73六章 結論與未來展望 86.1結論 86.2未來展望 86考文獻 8
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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