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Relative threshold tree pruning multi-user detection with user ordering and user partitioning for MC-CDMA
No full textWireless Recording System for Action Potentials
No full text本研究為神經動作電位無線記錄之初期研究，共分為兩部份：神經動作無線記錄系統與大鼠心率計量器之開發。實驗室目前電生理信號記錄系統是侷限於有線傳輸階段，連接電纜線至電極以記錄大鼠腦部受外部刺激之相關反應，本研究使用無線傳輸技術取代原本電生理實驗有線傳輸的方式，並且整合類比/數位轉換功能發展出高通用性的記錄系統。心率計量器的設計是為了能在電生理實驗中即時反應大鼠心跳次數而發展出一套麻醉深度輔助監控系統。 本系統為單通道神經動作電位無線記錄系統，結合了信號調控電路、外部觸發、類比/數位轉換以及藍芽傳輸等功能，可以應用於電生理實驗記錄與錄音帶資料備份記錄。依據不同實驗情況的電生理信號記錄，可修改微控制器韌體並將取樣頻率、傳輸速度以及資料擷取時間長度調整至實驗需求。 根據實際動物實驗量測，神經動作電位無線記錄系統與原本有線傳輸記錄系統所記錄到神經動作電位其相關係數高達0.999，証實本研究所開發的無線傳輸記錄器能取代原本的記錄系統，而大鼠心率計量器的監控也能得知麻醉深度是否適當，以維持電生理信號的穩定性。透過本研究的初步評估，本實驗室能基於此架構再繼續進行另一階段的多通道神經動作電位無線記錄系統的研究。The thesis is a pilot research of wireless recording system for action potentials. The system includes wireless recording system and heart rate meter (HR meter). In traditional recording system, evoked responses recording was transmitted through the cable. In this research, wireless recording system which includes wireless technique and A/D (Analog-to-Digital) converter was proposed to substitute the traditional cable transmissions. Furthermore, HR meter was designed for monitoring the anesthetic level of rat through detecting the heart rate with real-time display due to it affects the S/N ratio of electrophysiological signal seriously. The single-channel wireless recording system consists a precondition unit, external trigger, A/D converter, and Bluetooth module. This system can be used for simulation, off-line sampling and real-time electrophysiological recording. The microcontroller firmware that controls the sampling rate, baud rate and acquisition time could be adjustable for user according to different experimental requirements. After the actual experimental measurement, the correlation-coefficient between cable transmission and wireless recording is 0.999. HR meter that monitors the heart rate can help us to monitor the level of anesthesia of the rat during experiment. By use of this system, we might evaluate the feasibility of multi-channel wireless recording system in the future.圖目錄…………………………………………………………………Ⅲ目錄…………………………………………………………………Ⅴ文摘要………………………………………………………………Ⅵ文摘要………………………………………………………………Ⅶ一章 序論……………………………………………………………11.1 研究背景與動機…………………………………………………11.2 研究目的與介紹…………………………………………………2二章 研究方法與實驗設計…………………………………………42.1 神經動作電位無線記錄系統……………………………………42.1.1信號調控電路……………………………………………………62.1.2微控制器電路……………………………………………………72.1.3 無線傳輸模組…………………………………………………112.2 記錄模擬神經動作電位…………………………………………132.3 心跳計數系統……………………………………………………15三章 結果……………………………………………………………203.1 神經動作電位無線記錄系統……………………………………203.2 系統實際記錄結果………………………………………………233.3 HR Meter實際測試結果…………………………………………29四章 討論與結論……………………………………………………33考文獻………………………………………………………………3
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
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