1,720,954 research outputs found
Terpene classification using mass spectra data and machine learning
No full textTraditionally, separation and classification of terpenes from food samples is done with thehelp of two processes, namely: Gas Chromatography (GC) (separate terpenes from each other) and Mass Spectrometry (MS) (detects the separated terpenes). A mass spectrum is matched to known terpenes by a chemist using an existing database of various samples. We propose a machine learning solution that detects multiple terpenes from mass spectra without separating them. Synthetic data is generated using six common terpenes, cannabid-iol (CBD) and tetrahydrocannabinol (THC) using an additive composition model with five percent resolution in each component. The six base terpenes included in the current study are myrcene, linalool, limonene, α-pinene, β-pinene, and trans-caryophyllene, referred to as target chemicals. These terpenes are found in many food products that we consume in our day-to-day lives. There are 50,388 possible mass spectra combinations of these terpenes. The research investigates the development of a machine learning approach that classifies and quantifies the target chemicals. The system reads the mass spectra and automatically detects target chemicals that are present and determines their relative proportions. Various supervised and unsupervised classification and regression models are built and tested.Principal Component Analysis (PCA) of the eight target chemicals is performed to test how distinguishable the terpenes are. Classification of the major contributor target chemical with the help of artificial neural networks and a deep learning algorithm results in an accuracy of 99.1% for target chemicals respectively based on a train-test split methodology. Regression results with the help of ANNs and a single-layered model result in a mean absolute error of 0.001222 for target chemicals based on a train-test split methodology
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
Electrical Characterization of Thin-Film Polymer Tantalum Capacitors
Get PDFPolymer Hermetic Sealed (PHS) Tantalum capacitors are advanced Polymer Tantalum capacitors with moisture sealed in the capacitor via hermetically sealing the device inside a package. Their attractive features include high volumetric efficiency, leakage current stability, and low weight as compared to wet and solid-state polymer Ta capacitors. Moreover, recent studies have observed certain interesting properties in PHS Ta capacitors like Breakdown Voltage (BDV) being greater than Formation Voltage, anomalous transient currents, and Capacitance Stability issues. In this thesis, a technique to accurately perform the electrical characterization of thin-film MIS polymer Ta capacitors is established in order to understand the properties observed in PHS Ta capacitors. BDV greater than Formation Voltage is observed in these thin-film MIS capacitors which bolsters our hypothesis that this amazing phenomenon is primarily due to the material layers and their interactions, as opposed to being primarily due to the complex structure of KEMET’s PHS Ta capacitors. Moreover, Capacitance Stability is observed in thin-film MIS devices. The C(T) results are observed to be closely following the dielectric constant k(T) for almost the entire range of temperature, i.e., -55˚C to 150˚C. This result suggests that the thin-film MIS capacitors have capacitance dependence on temperature primarily due to the natural dependence of its dielectric material. In addition, Poole-Frenkel leakage mechanism is observed in some of the thin-film MIS capacitors. Thin-film MIS capacitors are established as viable, inexpensive, and easily fabricated models of KEMET PHS Ta capacitors to improve the Capacitance Stability and Breakdown Voltages of existing PHS Ta capacitors
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
