1,721,120 research outputs found
Chen Bi-sheng & Yang Guo-zhen, Chen Jia-geng zhuan
No full textChing-Fatt Yong. Chen Bi-sheng & Yang Guo-zhen, Chen Jia-geng zhuan. In: Archipel, volume 27, 1984. pp. 201-202
Chen Bi-sheng & Yang Guo-zhen, Chen Jia-geng zhuan
No full textChing-Fatt Yong. Chen Bi-sheng & Yang Guo-zhen, Chen Jia-geng zhuan. In: Archipel, volume 27, 1984. pp. 201-202
Bi sheng yin guan cong shu /
No full textIssued without general t.p.? Title from case. Cf. Zhonghua cong shu zong lu.Mode of access: Internet
Quadcopter Flow Field Research
No full text本論文旨在建立完整四旋翼飛行流場模型並觀察流場升力變化，此飛行流 場模型以四旋翼盤旋飛行為主要基本架構，再來加入標準外流場來模擬盤旋飛 行時的流場變化。首先根據文獻回顧，探討四旋翼的研究方向不外乎圍繞在控 制與效率上，並沒有針對其飛行流場變化進行研究。因此，為了便於觀察四旋 翼轉子旋轉時的流場升力變化，本研究以市售DJI F450 四旋翼來當作研究對 象，並將各轉子槳葉擺放相同的位置，以流場分析軟體Autodesk Simulation CFD 模擬整體流場並利用暫態分析，調整不同大小的風速與風向來分析四旋翼 轉子間的影響。結果顯示在盤旋飛行時，以恆定大小的風速從水平方向與從-30 度(-30 度為由上往下吹的夾角)方向吹拂，所造成的升力不均現象最為顯著。主 要造成水平風向升力不均的原因在於受渦流影響，而-30 度風向受速度加成影響 所致。This paper aims to establish a complete quadcopter flying flow model and observe the flow field of lift variation, the flight flow model uses quadcopter hovering flight as the basic infrastructure, added with the standard external flow field to simulate the flow field when hovering. First, according to the literature review, the research focus on control and efficiency, and has not been studied for its flight flow field. Therefore, in order to observe easily the changes in the lift of quadcopter rotor rotation, the research use commercial product DJI F450 as the main object and each rotor blade set the same location in the analysis software-Autodesk Simulation CFD. This simulation software uses transient analysis to analyze the whole flow field and adjust the wind speed and direction, in order to analyze the impact of the quadcopter. The results of this study show when hovering flight, the horizontal wind and -30 degrees wind direction (the -30 degrees means the angle between the wind blowing from top to bottom) causes the lift differential (Dissymmetry of lift) most significant
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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