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A New Spirobifluorene-Bridged Bipolar System for a Nitric Oxide Turn-On Fluorescent Probe
No full textThe Study of Acoustic Characteristics of Orthotropic Composite Laminates
No full text本篇論文主要探討非等向性複合材料平板之聲學性質，希望能藉由本研究更進一步了解複合材料板的聲波傳輸性質以及隔音效果。
本文使用傳輸矩陣法計算複合材料平板的聲音穿透損失，由於複合材料(FRP Fiber Reinforced Plastic)為異向性材料，而傳統的聲波傳輸矩陣法皆只適用於等向性材料，因此本文使用的為由傳統聲波傳輸矩陣推導延伸出可適用於非等向性複合材料的特殊傳輸矩陣。首先探討具橫斷面等向性的FRP，此部分使用的聲波傳輸矩陣為二維之數學模型。至於不具橫斷面等向性的FRP，則將二維數學模型擴展成三維。
由於在複合材料的應用上，常需依照使用需求的不同而採用不同的纖維積層製作複合材料，而傳統的聲波傳輸矩陣法皆適用於等向性材料且單一材質上，因此在本文中也進一步探討傳統傳輸矩陣應用在不同材料疊層上時，積層與積層之間邊界連續條件為應力連續或是應變連續的合理性，並以實驗驗證之。
另外，本文亦針對不同纖維編織方式之複合材料作機械及聲學特性的分析，進而計算出不同種類的纖維複合材料隔音效能，內容包括聲波入射複合材料表面之臨界角分析，以及複合材料積層板內的層間應力分佈，最後探討纖維補強型複合材料的積層順序對聲音穿透損失的影響。希望藉由本研究能對複合材料的聲學特性有更進一步的了解，進而廣泛應用。The principal purpose in this study is to investigate the sound characteristics of FRP (Fiber reinforced plastics) materials. In this work, TMM (Transmission matrix method) was applied to estimate the sound transmission loss of a FRP plate. However, FRP materials almost process orthotropic or anisotropic material properties but the traditional TMM is only suitable for isotropic material. Therefore, the sound wave equation of orthotropic plates is formulated in the study and than the special TMM that suits FRP laminate is used in this investigation. There are many kinds and types of FRP materials in the industrial applications. The FRP material properties are various among the different kinds of FRP. Thus, the TMM should be adjusted to suit each various FRP laminate. In the study, as the FRP plate possesses transverse isotropic in in-plane, the two-dimension mathematical model is appropriate to analyze the acoustic characteristics of the plate. If the FRP plate is fully orthotropic, the three-dimension mathematical model which extended from two-dimension model will be suitable to the calculation.
Further, at the boundaries between the layers of a FRP laminate, the discussion on boundary conditions is also analyzed with some experiments in the present work. There are two kinds of boundary conditions considered in the study, i.e. stress continuity and strain continuity. In the experimental results, the stress continuity is more appropriate to be used in the works than the strain continuity of boundary condition. Moreover, the other acoustic characteristics of FRP plates including the wave critical angle, the stress variations of each layer, and the sound transmission of the FRP plate were also estimated in the study
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
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