1,721,083 research outputs found
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
Measurement of the photovoltaic effect in sliding ferroelectric (PbS)1.11VS2
No full textTitle: Measurement of the photovoltaic effect in sliding ferroelectric (PbS)1.11VS2 Author: Soňa Cádrová Department: Department of Condensed Matter Physics Supervisor: RNDr. Klára Uhlířová, Ph.D., Department of Condensed Matter Physics Abstract: The subject of this bachelor thesis is the investigation of the photovoltaic effect in the ferroelectric layered material with asymmetric crystal structure (PbS)1.11VS2. Using AFM, moiré domains in (PbS)1.11VS2 were identified, originating from symmetry breaking between its layers. These domains play a key role in the generation and direction of the photocurrent in both the bulk and surface photovoltaic (photogalvanic) effects (BPVE, SPGE). (PbS)1.11VS2 demonstrated photovoltaic properties in bulk samples. The generated photocurrent in (PbS)1.11VS2 depends on the intensity and wavelength of the incident light beam. The influence of the ferroelectric domains in (PbS)1.11VS2 on the magnitude, polarity, and time profile of the photocurrent generation was also confirmed. The thesis discusses the measurement procedures, sample preparation, and their miniaturization for future photovoltaic investigation
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
Numerical simulations of optical response of nanostructures using FDTD method
No full textTitle: Numerical simulations of optical response of nanostructures using FDTD method Author: Ondřej Novák Institute: Institute of Physics of Charles University Supervisor: RNDr. Martin Veis, Ph.D., Institute of Physics of Charles University Abstract: Abstract: The aim of this thesis is to develope an efficient algorythm to compute optical response of nanostructures and to equip it with usefull tools for further data processing. Considered problem is reduced to two dimensions and the method used is the Finite Difference Time Domain (FDTD). This method operates on finite grid called Yee grid and is often called Yee algorithm. En extra emphasis is given on optimalization of the algorithm and writing the computer code efficiently. Evolution equations are written in tensor form and the core algorithm is moved to graphic card using CUDA. Various boundary conditions are introduced to reduce reflections on the edge of the grid. Representation of a real object on the Yee-grid is discussed with introduction of several smoothing methods to improve the shape convergence of simulated object. Useful post- processing methods are introduced - discrete Fourier transform, from which the frequency response of simulated object can be computed and a way to compute the far field from the near field. Finaly, there is an attempt..
Dynamic change in optical response of nanostructures
No full textTitle: Dynamic change in optical response of nanostructures Author: Michal Vančík Institute: Institute of Physics of Charles University Supervisor: RNDr. Martin Veis, Ph.D., Institute of Physics of Charles University Abstract: At the present time, properties of thin layers and multilayered nanos- tructures are intensively reseacrched. Because of different properties than bulk materials, thin layers have found application in various fields and play a key role in many technologies. Nanostructures containing GdOxare intensively studied since their properties can be modified by voltage application. It is assumed, that this change is caused by migration of ions in the structure. This thesis conducts re- search on multilayered structures, whose optical response changes reversibly by applying voltage. In these samples, the change is likely caused by migration of hydrogen ions into the GdOx layer. The goal of this thesis is to describe the opti- cal properties of individual layers of the structure and to describe the dynamic change in optical properties. The measurements were conducted with the help of spectroscopic ellipsometry, which allowed in situ voltage application. Keywords: spectroscopic ellipsometry, gadolinium oxide, multilayered nanostruc- tures, in sit
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
- …
