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A Generalized Floquet Theory for the Treatment of Electron Transport of Nanoscale Systems
No full text奈米尺度系統的電子傳輸常假設於寬帶極限之下，在此極限下，記憶效應會隨之忽略。在此論文中，我們將Floquet理論應用於奈米尺度系統之電子傳輸，探討在時變外加場之下記憶效應的多光子同調穿隧截止效應。以電極─雙量子點─電極系統為例，電極與量子點之交互作用假設為勞侖茲分佈函數時，探討記憶效應之影響以及多光子同調穿隧截止效應之物理機制。Electron transport through nanoscale systems are often studied in the wide-band limit without taking the memory effect into consideration. In this thesis, we present a novel Floquet approach in electron transport through nanoscale systems beyond the wide-band limit to explore the multi-photon (MP) coherent destruction of tunneling (CDT) with memory effect in the presence of time-dependent driving field. As a case study, the time-averaged current is calculated in an electrode-double quantum dots-electrode system driven by a periodic field using single Lorentzian spectral density function and a detailed analysis is presented to illustrate the origin of MP-CDT as well as the significance of memory effect.1 Introduction 1 Generalized Floquet Formalism and Quasienergy Methods 5.1 The Schrodinger Equation with Periodic Hamiltonian 6.2 Properties of Floquet Hamiltonian 9 Photon-Assisted Transport in nanoscale systems 13.1 Tien-Gordon Model 14.2 Nonequilibrium Green''s Function technique in mesoscopic systems 16.2.1 Model Hamiltonian 17.2.2 General expression for the current 19.3 Equation of motion approach to the electrode-wire-electrode system 22.3.1 Charge, current and current noise 24.3.2 The Heisenberg equation of motion 27.3.3 Lead elimination 30.3.4 Wide-Band Limit 38 Memory effect in nanoscale systems driven by a periodic field: A generalized Floquet approach 41.1 Lorentzian spectral density function 42.2 Reformulating equation of propagator using single Lorentzian spectral density model 45.3 Multi-photon coherent destruction of tunneling through double quantum dots using single Lorentzian spectral density function 50 Summary and perspective 63 Simple Proof of Floquet Theorem 65 Contour-ordered Green''s function 69.1 Time-ordered Green''s function 69.2 Contour-Ordered Green''s Function 71ist of Publications 77ibliography 7
Memory effect on the multiphoton coherent destruction of tunneling in the electron transport of nanoscale systems driven by a periodic field: A generalized Floquet approach
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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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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