1,720,988 research outputs found
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
Analytical solutions for the impedance of symmetrically distributed relaxation processes
No full textDistribution of relaxation times (DRT) analysis of impedance data is a powerful tool for unravelling entangled relaxation processes. However, reconstructing the DRT function from experimental data is an ill-posed inversion problem which suffers from noisy input and, hence, assigns a pseudo-signal to any kind of noise. To circumvent the resulting overfitting, different methods have been proposed, which are usually based on regularization.
Alternatively, carefully selected distributed basis functions (e.g. Gauss-type, Cauchy-type, Matern-type) can be included in the algorithm of DRT reconstruction. This concept originates from the work of Cuicci and coworkers and has been implemented in their great software package DRT-tools. While this works exceptionally well for minimizing the demand on regularization, it must be kept in mind that the impedance of real-world relaxation processes of the constant phase element type is not represented by any of the resulting DRT functions.
Bridging this gap was therefore the motivation for the present study. We derived analytical solutions for the impedance of several different types of distribution functions. The resulting impedances are compared with classical relaxation models and special features are pinpointed. The choice of an optimized basis function for reconstructing the DRT from experimentally acquired impedance data will improve electrochemical analysis in future work. Additionally, analytical solutions may be used for assigning a physical origin to the distributed behaviour in the impedance of certain types of electrodes
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
Low-Lying Electronic States of the Molecules AB_n (A = Sc-Ni, B = Cu/Ag/Au, n = 1, 2)
Get PDFA total of 561 electronic terms of 48 transition metal molecules AB_n (A = Sc - Ni, B = Cu/Ag/Au, n = 1, 2) were systematically studied using multireference configuration interaction (MRCI) technique. All-electron calculations, employing valence quadruple zeta basis sets, were performed incorporating scalar relativistic effects by means of the Douglas-Kroll-Hess (DKH) Hamiltonian. For diatomic molecules, full and smooth potential energy curves have been constructed at the DKH-CASSCF and DKH-MRCI(+Q) levels of theory, whereby observable molecular properties - such as equilibrium internuclear distance (r_e), harmonic frequency (omega_e), anharmonicity constant (omega_e x_e), dissociation energy (D_e), and dipole moment (mu_e) - have been reported. Spin-orbit coupling, core correlation effects, and basis set incompleteness have been probed for some selected systems. In order to assess the perturbative treatment of spin-orbit coupling at the DKH-MRCI(+SO) level of theory, spin-orbit coupling was dealt with variationally at the exact 2-component level of theory. A ground state binary relation between the atomic ion A+ and the diatomic molecule AB has been unveiled. For triatomic molecules, two sets of potential energy surfaces have been constructed using spline interpolation. The D_{infty h} and C_{2v} molecular structures and the connection between them, are pictured by the first set, symbolised by E (theta_{BAB}, r_{AB}; ^{2S+1}Gamma). The second set, E(r_{AB}, r_{BB}; ^{2S+1}Lambda), represents the linear ABB form. These are assessed, first, by considering the molecular stabilities with respect to the asymptotes A+B_2, AB+B, and A+2B - all being in ground state. Secondly, structure optimisation calculations have been performed for the lowest states in each isomer.Es wurden 561 elektronische Terme von 48 Übergangsmetall Molekülen AB_n (A = Sc-Ni, B = Cu/Ag/Au, n = 1,2) mit der Multireference Configuration Interaction (MRCI) systematisch untersucht. All-Elektron Rechnungen im Valenz quadruple zeta Basissatz wurden einschließlich skalar relativistischer Effekte mittels des Douglas-Kroll-Hess (DKH) Hamiltonian durchgeführt. Für zweiatomige Moleküle wurden vollständige und glatte Potential Energie Kurven auf dem DKH-CASSCF und DKH-MRCI(+Q) Niveau berechnet. Molekulare Eigenschaften - wie internuklearer Gleichgewichtsabstand (r_e), harmonische Frequenz (omega_e), Anharmonizitätskonstante (\omega_e x_e), Dissoziationsenergie (D_e), und Dipole Moment (mu_e) - wurden angegeben. Spin-Bahn-Kopplung, Kern Korrelations Effekte, und der Effekt unvollständiger Basissatz wurden für ausgewählte Systeme untersucht. Für die störungstheoretische Behandlung der Spin-Bahn-Kopplung auf dem DKH-MRCI(+SO) Niveau, wurde die Spin-Bahn-Kopplung variationel auf dem Niveau der exakte 2-Komponenten Dirac Gleichung durchgeführt. Im Grundzustand wurde eine binäre Beziehung zwischen dem einatomigen Ion A+ und dem zweiatomigen Molekül AB entdeckt. Für dreiatomige Moleküle wurden zwei Sätze von Potential Energie Flächen mittels kubischer Spline Interpolierung konstruiert. Der erste Satz bildet die molekularen D_{infty h} und C_{2v} Strukturen und ihre Beziehung sind ab, symbolisiert durch E(theta_{BAB}, r_{AB}; ^{2S+1}\Gamma). Der zweite Satz, E(r_{AB}, r_{BB}; ^{2S+1}Lambda), repräsentiert die lineare ABB Form. Sie wurden zunächst bewertet durch Betrachtung der molekularen Stabilität in Bezug auf die Asymptoten A+B_2, AB+B, und A+2B - alle im Grundzustand.Außerdem wurden Strukturoptimierungen für die niedrigsten Zustände jedes Isomers durchgeführt
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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