1,720,963 research outputs found
Giant Magnetoresistance in a Single Thin Film of Permalloy
Get PDFFaculty adviser: Prof. Dan DahlbergAn experiment was constructed to measure giant magnetoresistance (GMR) in a 100-nm thick film of permalloy. After removing competing effects such as anisotropic magnetoresistance and eliminating all false positive signals, measurements indicate the presence of a domain wall but no definitive GMR signal. Alternative methods are in progress, which will hopefully resolve the difficulties with the initial measurement.This research was supported by the Undergraduate Research Opportunities Program (UROP).Gray, Isaiah. (2013). Giant Magnetoresistance in a Single Thin Film of Permalloy. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/36760
AC Magnetic Susceptibility of a Permalloy Thin Film
No full textFaculty advisor: Dan DahlbergMeasurements of noise in magnetic thin films have variously reported noise, white noise, and random telegraph noise. The noise experiments claim magnetic noise by relating the magnetic noise to the susceptibility with use of the fluctuation-dissipation theorem. However, neither the linearity of the susceptibility necessary for application of fluctuation-dissipation nor the frequency dependence of susceptibility was explored. To investigate more fully the frequency dependence and linearity of the magnetic susceptibility of a magnetic film, we measured the AC susceptibility of a 100 nm thick film of permalloy as a function of the magnitude and frequency of an applied AC magnetic field over the full hysteresis loop of the films, i.e., the measurements were performed while slowly varying an applied DC magnetic field, . The AC frequency range was from 20 Hz to 5 kHz while the AC field range was between 0.2 G and 1 G. At the response of the system was measured as a function of at 200 Hz. It was found to be nonlinear but became reasonably close to linear for - the coercive field was approximately 15 G. The in-phase and out-of-phase components approximately follow power laws with frequency, with exponents 0.69 and -0.2. The behavior of the out-of-phase component is roughly consistent with previously measured white magnetic noise and a simple harmonic oscillator model, but the in-phase component does not follow the prediction of this model.This research was supported by the Undergraduate Research Opportunities Program (UROP).Gray, Isaiah. (2014). AC Magnetic Susceptibility of a Permalloy Thin Film. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/163159
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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