1,722,294 research outputs found
Public opinion survey in Hong Kong
No full textThe data were collected in the project funded by grants from Policy Innovation and Co-ordination Office Public Policy Research (PPR) Funding Scheme (Special Round), Hong Kong SAR (Project Number SR2020.A5.028)
sj-docx-1-ejo-10.1177_11206721231208244 - Supplemental material for Association between optic atrophy 1 polymorphisms and primary open angle glaucoma risk: Based on a meta-analysis
No full textSupplemental material, sj-docx-1-ejo-10.1177_11206721231208244 for Association between optic atrophy 1 polymorphisms and primary open angle glaucoma risk: Based on a meta-analysis by Yue-Feng Liu, Xiang-Yu Luo, Zhi-Cai Zhao, Wu Zheng, Hai-Yang Lv and Wei-Min Luo in European Journal of Ophthalmology</p
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
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
Synthetic Spectrum Harmonic Imaging
No full text組織諧波成像比起傳統的基頻成像，已證實能改善超音波影像品質，在對比度與空間解析度得到明顯提升，在臨床上乳房與甲狀腺的諧波成像已在使用，而諧波訊號的產生機制，在於超音波在組織傳遞過程中，波形會產生有限幅變形，然而組織諧波強度再強也不會超過基頻強度，諧波強度是遠小於基頻強度的，所以諧波成像最大問題在於信雜比不足導致穿透深度受限制，若能改善諧波信雜比強度的話，將能增加深層組織的可視性。
傳統上諧波成像的發射訊號為簡單脈衝波，而脈衝波要得到高解析度影像，其發射訊號必須為大頻寬的短脈衝波，但這樣會造成發射訊號強度下降，而編碼技術能提高發射訊號強度，增強諧波訊號的信雜比，而編碼技術有著空間上旁辦假像問題，旁辦假像產生原因在於頻譜上諧波成份與基頻成份重疊，所以需透過其他方法抑制基頻，目前壓抑基頻產生最有效方式為脈衝反相技術，可使旁辦假像問題壓至最低，但編碼技術使用在臨床上仍有問題，問題在於組織衰減影響，所以再發射與接收時需補償，但編碼技術在補償做法較困難。
而本研究提出的諧波合頻技術同樣能提高諧波的信雜比，重要的是在發射與接收的補償做法容易，諧波合頻技術做法為發射多個不同頻率的窄頻寬長脈衝 訊號，利用帶通濾波器將回波中的諧波成份濾出，用諧波訊號相加做合頻，實際上在組織內這些不同頻率諧波訊號一樣會受到衰減的影響，衰減的原因主為探頭與組織影響，而發射窄頻寬的好處為可視為單一常係數做補償，而論文中會探討諧波合頻原理，與諧波合頻問題，並進一步的改善。Tissue harmonic imaging has demonstrated that it can provide superior image quality compared to conventional fundamental imaging, contrast and spatial resolution can be substantially increased. Harmonic imaging has been used for detecting thyroid and breast. Harmonic generation mechanism of the acoustic wave propagates in tissues of the waveform distortion. However tissue harmonic intensity remains lower than that of the fundamental intensity, harmonic intensity is smaller than the fundamental intensity, so Tissue harmonic imaging suffers from the signal-to noise ratio(SNR) degradation, resulting in limited penetration depth . If there is a way can improve the harmonic signal SNR, Enhance the SNR could further improve the visualization of tissue at depth.
Traditionally, the transmitted signal as a pulse in harmonic imaging, the pulse to obtain high-resolution images, the transmitted signal must be wideband pulse, but this will result in degradation of the transmitted energy. Coded excitation can improve the transmitted energy, it can enhance to harmonic signal SNR, but coded excitation could suffer from the increased sidelobe artifact, caused by the spectral overlap between the fundamental and harmonic components. So need to suppress the fundamental frequency through other methods. According to research, pulse inversion shows the best result to suppress the fundamental frequency, effective rejection of the sidelobe artifact. Coding excitation still has problems on the clinical. The problem is attenuation in tissue. So to be compensated on transmit and receive, however coding excitation hard to compensate.
In my research, synthetic spectrum also can improve the harmonic signal SNR. It’s important to compensate easily. In Synthetic Spectrum, more pulses are transmitted with different frequencies. Use a Band-pass filter to get harmonic components. Sum of harmonic signals is synthetic spectrum. In fact different frequency harmonic signals will attenuate in the tissue. The main reason for attenuation is Transducer and tissue. Narrow bandwidth of transmission signal can be regarded as constant coefficient compensation. This paper will explore the basic principles of synthetic spectrum for further to improve
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