1,720,954 research outputs found
Investigating dimensionally-reduced highly-damped systems with multivariate variational mode decomposition : an experimental approach
Get PDFThis paper has been withdrawn by Mehulkumar Rajkumar Lakhadive We have identified significant methodological and mathematical inconsistencies in the current formulation of the paper, particularly in the absence of the optimization framework that is crucial to the core analysis. These issues may lead to misinterpretation of the proposed approach. We are currently working on a revised and complete version that accurately reflects the intended contributions Structural health monitoring (SHM) is an essential engineering field aimed at ensuring the safety and reliability of civil infrastructures. This study proposes a methodology using multivariate variational mode decomposition (MVMD) for damage detection and modal identification. MVMD decomposes multi-sensor vibration responses into intrinsic modal components, facilitating the extraction of natural frequencies and damping ratios by analyzing amplitude decay in the identified modes. Mode shapes are determined through peak-normalization of Fourier spectra corresponding to each mode. The methodology is further applied to detect damage by identifying changes in the extracted modal parameters and spatial features of the structure. The proposed approach enables damage detection by tracking variations in modal parameters and spatial structural characteristics. To validate its efficacy, the methodology is applied to a benchmark eight-degree-of-freedom (8-DOF) system from Los Alamos National Laboratory (LANL), demonstrating its robustness in identifying structural damage under non-stationary excitation and narrowband frequency content. The results confirm that MVMD provides a reliable and adaptable framework for modal analysis and damage assessment in complex infrastructure systems, addressing key challenges such as environmental variability and practical scenarios
FAME–SSA : a Fast Adaptive Multivariate Decomposition Method for unsupervised damage detection in built infrastructures
Get PDFStructural Health Monitoring (SHM) techniques are continuously challenged by the complexities and noise inherent in large-scale multidimensional data. Empirical Mode Decomposition (EMD) is effective for non-stationary signals but struggles with multichannel data. Multivariate EMD (MEMD) addresses this but still suffers from noise sensitivity, mode mixing, and incomplete frequency extraction. Fast and Adaptive Multivariate EMD (FA-MVEMD) improves on MEMD by using intelligent strategies to enhance accuracy and performance. This study introduces a novel methodology for modal identification and damage detection: Fast and Adaptive Multivariate Empirical Singular Spectrum Analysis (FAME-SSA). By combining the adaptive decomposition capability of FA-MVEMD with the trend extraction and noise separation strengths of Singular Spectrum Analysis (SSA), the proposed approach improves the accuracy and robustness of feature extraction from structural responses. A key innovation of FAME-SSA is the application of Hotelling’s T² and Squared Prediction Error (SPE) statistics for damage detection. The method is validated through extensive numerical simulations, experimental data from a wind turbine structure, and real-world SHM data from the Lysefjord Bridge. The results demonstrate that FAME-SSA outperforms conventional methods, making it a promising tool for real-time SHM in complex and noisy environments under challenging conditions
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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