1,720,963 research outputs found
Tomographic X-ray data of time-dependent 3D cross phantom
No full textThis is the documentation of the tomographic X-ray data of a dynamic cross phantom made available at http://www.fips.fi/dataset.php. The data can be freely used for scientific purposes with appropriate references to the data and to this document in http://arxiv.org/. The data set consists of (1) the X-ray sinogram with 16 or 30 time frames (depending on resolution) of 2D slices of the cross phantom, made by crossing aluminum and graphite sticks in melted candle wax and (2) the corresponding static and dynamic measurement matrices modeling the linear operation of the X-ray transform. Each of these sinograms was obtained from a measured 360-projection fan-beam sinogram by down-sampling and taking logarithms. The original (measured) sinogram is also provided in its original form and resolution.
This new version contains added file DataStatic_560x60.mat with 80 time frames and DataStatic_1120x60.mat with 230 time frames. You can run these files with the code example 2, which computes a Tikhonov regularized reconstruction using conjugate gradient algorithm.</p
Tomographic X-ray data of time-dependent 3D cross phantom
No full textThis is the documentation of the tomographic X-ray data of a dynamic cross phantom made available at http://www.fips.fi/dataset.php. The data can be freely used for scientific purposes with appropriate references to the data and to this document in http://arxiv.org/. The data set consists of (1) the X-ray sinogram with 16 or 30 time frames (depending on resolution) of 2D slices of the cross phantom, made by crossing aluminum and graphite sticks in melted candle wax and (2) the corresponding static and dynamic measurement matrices modeling the linear operation of the X-ray transform. Each of these sinograms was obtained from a measured 360-projection fan-beam sinogram by down-sampling and taking logarithms. The original (measured) sinogram is also provided in its original form and resolution.</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
MODEL MANGSA PEMANGSA DENGAN MANGSA TERINFEKSI DI LINGKUNGAN BERACUN
No full textModel of predator-prey with infected prey in toxical environment is discussed in
this thesis. The objective of this research are to find out whether each of populations is
extinct or not and to know the existence of toxicant concentration.
In this thesis, two models are constructed, those are, model of prey predator with
infected prey and model of prey predator with infected prey in toxical environment.
Toxicant affects the growth rate of susceptible and infected prey but not affects the
growth rate of predator population.
There are four equilibrium points in the model of prey predator with infected prey.
With appropriate parameter value and any initial value near equilibrium points, then
for a long time, there are three possibilities, those are the infected prey and predator
will be extinct and susceptible prey will be existent, the susceptible prey and predator
will be existent and the infected prey will be extinct, or the only population that will be
extinct is predator population. Then, with appropriate parameter value, for a long time,
the susceptible and infected prey and predator population will be existent for any
initial value. In the model of prey predator with infected prey in toxical environment,
there are four equilibrium points. With appropriate parameter value and any initial
value near equilibrium points, then for a long time, there are three possibilities, those
are only the infected population that will be extinct, only the predator population that
will be extinct, or the infected prey and predator population will be extinct. Then, with
appropriate parameter value, for a long time, susceptible and infected prey population
and predator population will be existent for any initial value. Numerical simulation is
given to ilustrate stability behaviour of equilibrium point
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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