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Huaren shehui daren xixia you ming Huaren shehui de bing
No full textDe Beer-Luong Brigitte. Huaren shehui daren xixia you ming Huaren shehui de bing. In: Archipel, volume 25, 1983. pp. 234-235
High-quality mipmapping texture compression with alpha maps for graphics processing units
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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
Synthesis and Characteristics of Organic Light-emitting Materials Based on Fluorene and Carbazole
No full text利用簡易的合成方法，成功合成出以芴及咔唑為主體之主體(host)發光材料 DFCO 及 DFCN。在咔唑之3號及6號位置引入芴之基團，希望能在結構上增加其熱穩定性，同時限制其共軛長度，使其成為具有高三重態能量之主體發光材料。在電化學上，其具有穩定且可逆的氧化電位。TGA 可達 450 oC，Tg 則可達 180 oC。應用於有機發光二極體之元件上，在摻雜綠光及紅光之磷光材料後，皆有不錯之效率。
利用Suzuki偶合反應合成出具極高分子量之聚芴材料。透過單體分子的特殊設計以及Suzuki聚合條件的最佳化，成功的合成出分子量近九萬之聚芴發光材料。Herein, we report a series of novel electrophosphorecent host materials which hybridize the structure characteristics of carbazole and fluorene. Combining the properties such as high ambipolar charge carrier mobility of fluorene, and the low carrier injection barrier of carbazole can be reasonably anticipated to afford novel host materials. Through the deliberate molecular design, we can combine both characteristics of carbazole and fluorene independently. In this section, highly efficient and stable green and red eletrophosphorecent devices have been achieved using the compound DFCO as a host material.
In the second section, polyfluorenes were synthesized via palladium- catalyzed Suzuki coupling reaction. The introduction of alkoxyphenyl group on the 9-position of fluorene were not only avoid “keto defect” but also provide the solubility of the polymer. The weight average molar mass of PF1 can reach to 90000 and it could be a potential candidate for a pure blue light emitting polymer in PLED devices. PF2 with UV range emission could be a potential UV light emitter in OLED devices.目錄 i
表目錄 iv
圖目錄 v
中文摘要 viii
英文摘要 x
化合物編號索引 xii
第一章 緒論 1
1-1有機發光二極體發展歷史 1
1-2有機電致發光元件構造與發光原理 3
1-3多層結構中常見之材料 4
1-4客發光體（Guest Emitter） 10
1-5高分子材料 14
第二章 以芴及咔唑為主體之有機共軛發光材料之設計與合成 18
2-1以芴及咔唑為主體之主體（Host）材料之設計與合成 19
2-2以芴為主體之有機共軛高分子材料之設計與合成 24
第三章 實驗結果與討論 31
3-1實驗合成結果 31
3-1-1以芴及咔唑為主體之主體（Host）材料之合成結果 31
3-1-2以芴為主體之有機共軛高分子材料之合成結果 34
3-2以芴及咔唑為主體之主體（Host）材料之性質研究 39
3-2-1光物理性質 39
3-2-2 電化學性質 42
3-2-3 估計HOMO、LUMO能階值 46
3-2-4 熱性質 47
3-2-5 有機電致發光元件製備與性質 51
3-3以芴為主體之有機共軛高分子之性質研究 58
3-3-1光物理性質 58
3-3-2 電化學性質 59
3-3-3 估計HOMO、LUMO能階值 61
3-3-4 熱性質 62
第四章 結論與未來展望 65
第五章 實驗部份 67
5-1 測試儀器 67
5-2 實驗步驟與數據 70
參考文獻 80
附錄Ⅰ 86
附錄Ⅱ：化合物之1H及13C NMR 光譜圖 8
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
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