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Antenna Distance Analysis and Design for Wider Angle Detection for Mono-pulse Continuous Wave Doppler Radar and Characterization of High Frequency Transmission Line On Flexible Substrate
No full text本論文前兩章節將在低溫陶瓷共燒中給予的有限面積以及印刷電路板裡，實現雷達系統的被動元件布局，放置使用於同時擁有一個傳送以及兩個接收天線的單脈衝雷達探測系統，利用都普勒現象量測物體的移動速度，以及兩接收天線由於空間造成的差與和模態得到單脈衝訊號比例進行待測物的角度探測，並且將生物的生命現象於訊號中萃取出來。
由於要做到縮小化而且在面積有限的情境下，兩接收天線的間距已經小於一個波長，天線之間的距離對於場型有了很重大的影響，此時隔離度也成了一個無法忽略的問題，因此利用了天線的陣列設計理論與實際天線因為隔離問題導致偏離正上方的輻射場型對於實際接收到的射頻訊號做了更精確地分析。
以上所提出的所有設計理論及天線架構的細節，模擬與實驗驗證，於本論文中都會加以仔細地討論。
第三章與第四章將探討製作於軟性基板上的傳輸線特性。由於層層堆疊的基板在製程上較單層板困難且價格昂貴，在現在這種價格戰時代，可扭曲材質便顯現出了它的優點。另外材質的可扭曲性也因為行動裝置的需求量增加有了新的應用。例如將電路製作於軟性基板上並且應用在手錶等等的行動裝置，以佩帶於手上。
首先會介紹軟性基板的製程，如何生產出此種材料，以及電路製作過程和材料參數。接著是量測的介紹，因為在種種量測儀器的輔助下量測出的S參數並非真正待測物本身的S參數。本論文使用TRL校準方法便是用於此，透過三種長度thru、reflect，line的線解出我們必須得到的參數。
第四章的前半段是傳輸線的模擬結果以及重要參數例如S參數，傳輸線損耗等等的特性，接著透過量測將基板的介電係數和介電損耗準確地得出，再將其結果導入模擬，讓模擬結果與量測結果一致，完成特性研究。
最後一章總結兩個部分並且提出未來的願景。Two antenna layouts are realized in two different kinds of fabrication process which are LTCC (low temperature co-fired ceramics) and PCB (printed circuit board) in a limited area for monopulse radar system that includes one transceiving and two receiving antennas. The radar system uses Doppler effect to determine the speed of the target and the monopulse ratio which is determined by radiation modes of sum and difference pattern to detect the angle of the target.
Due to limited area, two receiving antennas are forced to place in the distance smaller than a wavelength, the isolation between two receiving antennas becomes a big issue that we can’t be ignored. I obstruct the radiated pattern away from the broadside direction. So we use the antenna theory to reconsider the signal we may receive in order to have a reliable measurement.
The operating mechanism and details of the antenna design are discussed. Experimental and simulated results are both presented and discussed.
The 3rd and 4th Chapter will discuss the characteristic of the transmission lines fabricated on flexible substrate, because of the difficulty and price issue, multilayer substrate is not comparable with single layer substrate. Take the advantage of the flexibility of the transmission line, we can connect substrate with it to accomplish a new 3D package.
In this part, we will first introduce the fabrication process, how to produce these materials and their parameters. Then the second part is the introduction of the measurement. TRL calibration method is used to remove the error caused by equipment we used in measurement.
At 4th chapter, it will show scattering parameters. By the measurement results we can get permittivity and loss tangent. Comparison between measurement and simulation will also be presented.
The last chapter is the conclusion of this thesis and the future work.目錄
中文摘要 iii
圖目錄 vi
表目錄 x
第一章 雷達簡介與基礎天線理論 1
第一節 動機 1
第二節 單脈衝連續波雷達 2
第三節 微帶型天線介紹 5
第四節 天線陣列 8
第二章 製程環境介紹與天線設計 13
第一節 製程環境 13
第二節 天線結構與設計 14
第三節 量測環境與校準 33
第四節 結果與討論 38
第三章 軟性基板簡介與量測方法 39
第一節 動機 39
第二節 軟性基板製程原理 40
第三節 TRL校準原理 41
第四章 傳輸線模擬與量測 45
第一節 傳輸線設計與模擬結果 45
第二節 量測結果 61
第三節 材料參數 65
第五章 結論與未來展望 68
第一節 結果與探討 68
第二節 未來工作 6
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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