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Diffuse Optical Tomography: Optode Design and Clinical Study
No full text本篇論文中設計了一套擴散光學斷層掃瞄術的系統，擴散光學斷層掃瞄術是利用近紅外光來觀測生物體內吸收係數、散射係數分佈的一套技術，能精確地描繪出生物組織中含氧血紅素、缺氧血紅素濃度以及血氧飽和度的變化狀態。
以軟性電路板作為主要的底材，將光源與光偵測器以棋盤式的幾何位置安置於其上，利用時間多工的方式使光源輪流發亮，再擷取光檢測器上的光強度作為影像重建的資料來源。
文中對健康的案例及一些加護病房中的病患做了一些生理量測實驗，主要是在靜脈束縛的觀察上，得到的實驗數據與真實的生理資訊有相當程度的對應性，且在特定病例上能看出與常人的差異性。Diffuse optical tomography (DOT) is the technique that probes and images spatial variations in absorption and scattering properties of the biological tissues. DOT can accurately measure simultaneous changes in concentrations of oxy-hemoglobin and deoxy-hemoglobin. The oxygenation images have been reconstructed by the measured hemodynamics signals with nearest-neighbor pairs of sources and detectors. In our study, a portable DOT system is built with optode design on flexible print circuit board (PCB). The DAQ card is used to PC connection for multiplex driving of laser diodes and detected signal process form photodiodes on optode in DOT system.
In this thesis, the principles and systematic designs of DOT are demonstrated. In experiments, the excise and vessel occlusion hemodynamics are observed with in vivo measurements form normal subjects and some patients in intensive care unit.誌謝……………………………………………………………….i
摘要………………………………………………………………ii
Abstract………………………………………………………….iii
目錄……………………………………………………………...iv
圖目錄…………………………………………………………..vii
表目錄…………………………………………………………...ix
第一章 緒論……………………………………………………1
1.1 生醫影像技術………………………………………………..….1
1.1.1 X射線輻射造影技術……………………………………...1
1.1.2 磁振斷層掃瞄術…………………………………………...2
1.1.3 電腦斷層掃瞄術…………………………………………...2
1.1.4 超音波造影技術…………………………………………...3
1.1.5 正子放射斷層掃瞄術……………………………………...3
1.1.6 光學同調斷層掃瞄術……………………………………...4
1.1.7 擴散光學斷層掃瞄術……………………………………...4
1.1.8 小結………………………………………………………...5
1.2 文獻回顧…………………………………………………………7
1.3 研究動機………………………………………………………..12
第二章 擴散光學斷層掃瞄術………………………………..13
2.1 光子遷移………………………………………………………..13
2.2 近紅外光光譜學………………………………………………..15
2.3 擴散光學斷層掃瞄術…………………………………………..16
2.3.1 擴散方程式………………………………………………...16
2.3.2 Modified Beer-Lambert Law………………………………..17
2.4 擴散光學斷層掃瞄術的系統分類……………………………..19
2.4.1 時域式擴散光學斷層掃瞄術………………………….…19
2.4.2 頻域式擴散光學斷層掃瞄術………………………….…20
2.4.3 連續波擴散光學斷層掃瞄術………………………….…21
2.4.4 三類系統的比較………………………………………….21
第三章 系統架構………………………………………………23
3.1 儀器設備………………………………………………………..23
3.2 探測器…………………………………………………………..23
3.2.1 雷射二極體……………………………………………….24
3.2.2 光檢測器………………………………………………….24
3.3 探測器與電腦間的連接介面…………………………………..26
3.3.1 資料擷取卡……………………………………………….26
3.3.2 訊號產生器、電源供應器及排線………………………..27
3.3.3 雷射二極體驅動電路…………………………………….27
3.4 訊號擷取的設定………………………………………………..28
3.5 二維影像重建…………………………………………………..29
3.6 LabVIEW程式介面……………………………………………30
3.7 系統可改進空間………………………………………………..32
3.7.1 雷射二極體間的距離差………………………………….33
3.7.2 軟性電路板的材質……………………………………….33
3.7.3 排線長短對訊號造成的影響…………………………….34
3.7.4 光檢測器的放大增益…………………………………….34
第四章 實驗結果與討論………………………………………36
4.1 系統效能量測…………………………………………………..36
4.2 實驗方法………………………………………………………..36
4.3 運動狀態………………………………………………………..37
4.4 血管束縛………………………………………………………..39
4.5 病例……………………………………………………………..44
4.6 討論……………………………………………………………..46
4.6.1 系統的可重複性………………………………………….47
4.6.2 實驗誤差的原因………………………………………….47
第五章 結論……………………………………………………49
參考文獻………………………………………………………..5
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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