1,720,969 research outputs found
The Geometry of Diet: Using Projections to Quantify the Similarity Between Different Sets of Dietary Patterns
No full textAim: Comparability represents one of the key problems that has been identified in dietary pattern analysis. With regard to traditional dietary pattern measurement, the following limitations have been observed:
1. Usually, the traditional method, which considers the comparisons of different
questionnaire types and different time points, seldom compares different populations.
2. Although the traditional method reflects the comparability in a single dietary
pattern, it cannot compare the scenarios that comprise multiple dietary patterns.
Therefore, to broaden the applications of dietary pattern measurement, an advanced
metric is necessary.
Method: Tucker’s congruence coefficient, a traditional method, focuses on the level of
similarity between the characterized patterns. The coefficient, which is specific to
extraction of patterns via principal components or factor analysis, is calculated by the
cosine value of the angle between a pair of principal components (PCs), which can be
considered as the projection from one PC to another. Herein, by generalizing the
projection concept to higher dimensional spaces, we propose an advanced Tucker’s
congruence coefficient. For two pairs of PCs (two dietary patterns), we implement the
projection from one plane to another, where each plane consists of two PCs from the
same survey. Similarly, because the three PCs obtained from one survey constitute one
cube, the coefficient entails the projection from one cube to another. Moreover, we
explored the rotation of PCs and observed that the proposed method is invariant when
applying rotation before projection, and we proved the reversibility and symmetry of
the method in the geometric space. Furthermore, using formula derivation, we
provide the comparability measurement for any dimensional principal components. To
utilize the proposed method, an R package (adt), which is available at
https://github.com/Fan-shiyu/adt, is developed.
Results: By truncating principal components, we implemented error analysis; the
proposed method performs optimally when the truncation threshold is below 0.15.
We collected 19 examples of repeatability and validity exercises from the dietary
patterns literature; therein, 13 effective data sets with acceptable threshold that can
compute the proposed metric exist. Moreover, we implemented the proposed metric
in the FFQ1 vs FFQ2, FFQ vs DR, and Men vs Women scenarios, where FFQ denotes
food frequency questionnaire and DR denotes dietary record, and we compared the
metric using other typical metrics including correlation, congruence coefficient, and
kappa coefficient.
Conclusion: This study developed an advanced metric with extended comparability of
dietary patterns. It can capture the information of multidimensional principal
components and provide more comprehensive and accurate measurements of dietary
patterns. In the future, the proposed metric can be applied with other typical dietary
metrics to jointly measure the validity of a diet survey
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
Data-based modal space control for active damping
No full textThis research presents a novel data-based modal control method for actively dampening the flexible mode in a multi-input multi-output (MIMO) system. Traditional passive damping methods add significant mass to the system, making recent advances in sensor and actuator technology, such as lightweight piezoelectric materials, a more appealing solution. The key contribution of this research is a novel modal decoupling method for active damping that uses the MIMO frequency response function to circumvent the need for a parametric model. This method facilitates the design of a single-input, single-output (SISO) controller that actively dampens a flexible mode using all available sensors and actuators. This approach significantly reduces the complexity of the controller design and tuning effort compared to the conventional decentralized control architecture. Experimental validation is carried out on a cantilever beam, which shows near-perfect isolation of the mode of interest. The study's findings may offer critical insights for future mechatronics systems, enabling the creation of more efficient and powerful machines.Mechanical Engineering | Mechatronic System Design (MSD
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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