1,720,963 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
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
Measurements of hadron yields from the T2K replica target in the NA61/SHINE experiment for neutrino flux prediction in T2K
No full textT2K is an accelerator-based long-baseline neutrino experiment in Japan. The main goal of the T2K experiment is a search for CP violation in the lepton sector by measuring electron (anti)neutrino appearance in a muon (anti)neutrino beam. Initial (anti)neutrino flux is produced in decays of hadrons which originate from the interactions and the re-interactions of a GeV proton beam with a cm long graphite target. Knowledge of the T2K neutrino flux is limited due to large hadron production uncertainties. A series of hadron production measurements were done to solve this problem, in the NA61/SHINE experiment at CERN. Measurements were performed with a proton beam and two target types: a thin graphite target and a replica of the T2K target. Work presented in this thesis concentrates on the T2K replica target data taken in 2010 and the development of the analysis and calibration software. The aim of these measurements is to fully constrain production of , , , and coming from the target surface by measuring differential hadron yields in the bins of outgoing particle momentum (p), polar angle () and longitudinal position on the target surface (). This will allow reduction of the T2K neutrino flux uncertainties from around to below . Predictions of Fluka2011.2c.5 Monte Carlo, NuBeam and QGSP_BERT physics lists from Geant4.10.03 have been compared to the data, and it has been found that Fluka2011.2c.5 gives the best prediction
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
Mesures des rendements en hadrons de la cible de réplique T2K dans l'expérience NA61/SHINE pour la prédiction du flux de neutrinos dans T2K
No full textT2K is an accelerator-based long-baseline neutrino experiment in Japan. The main goal of the T2K experiment is a search for CP violation in the lepton sector by measuring electron (anti) neutrino appearance in a muon (anti)neutrino beam. Initial (anti) neutrino flux is produced in decays of hadrons which originate from the interactions and the re-interactions of a 30 GeV proton beam with a 90 cm long graphite target. Knowledge of the T2K neutrino flux is limited due to large hadron production uncertainties. A series of hadron production measurements were done to solve this problem, in the NA61/SHINE experiment at CERN. Measurements were performed with a proton beam and two target types: a thin graphite target and a replica of the T2K target. Work presented in this thesis concentrates on the T2K replica target data taken in 2010 and the development of the analysis and calibration software. The aim of these measurements is to fully constrain production of π+ , π− , K+ , K− and p coming from the target surface by measuring differential hadron yields in the bins of outgoing particle momentum (p), polar angle (θ) and longitudinal position on the target surface (z). This will allow reduction of the T2K neutrino flux uncertainties from around 10% to below 5%. Predictions of Fluka2011.2c.5 Monte Carlo, NuBeam and QGSP_BERT physics lists from Geant4.10.03 have been compared to the data and it has been found that Fluka2011.c2.5 gives the best prediction.T2K est une expérience de neutrinos à longue ligne de base à base d'accélérateurs au Japon. Le but principal de l'expérience T2K est la recherche d'une violation de la PC dans le secteur du lepton en mesurant l'apparence (anti)neutrino des électrons dans un faisceau muon (anti)neutrino. Le flux (anti) neutrino initial est produit par les désintégrations des hadrons qui proviennent des interactions et des ré-interactions d'un faisceau de protons de 30 GeV avec une cible en graphite de 90 cm de long. La connaissance du flux de neutrinos T2K est limitée en raison des grandes incertitudes liées à la production de hadrons. Une série de mesures de production d'hadrons a été effectuée pour résoudre ce problème, dans l'expérience NA61/SHINE au CERN. Les mesures ont été effectuées avec un faisceau de protons et deux types de cibles : une cible en graphite mince et une réplique de la cible T2K. Les travaux présentés dans cette thèse se concentrent sur les données cibles de la réplique T2K prises en 2010 et sur le développement du logiciel d'analyse et d'étalonnage. Le but de ces mesures est de contraindre complètement la production de π+, π+, π-, K+, K+, K- et p provenant de la surface cible en mesurant les rendements différentiels en hadrons dans les cellules du momentum de particules sortant (p), l'angle polaire (θ) et la position longitudinale sur la surface cible (z). Cela permettra de réduire les incertitudes du flux de neutrinos T2K d'environ 10 % à moins de 5 %. Les prédictions de Fluka2011.2c.5 Les listes de physique Monte Carlo, NuBeam et QGSP_BERT de Geant4.10.03 ont été comparées aux données et il a été constaté que Fluka2011.c2.5 donne la meilleure prévision
and Analysis in Proton-Carbon Collisions at GeV/
No full textNA61/SHINE is a large hadron spectrometer located at North Area of CERN-SPS. There are 3 physics goals persuaded by NA61: search for the critical point of strongly interacting matter, hadron production measurement for the T2K neutrino experiment in Japan and measurements for the Piere-Augere and KASCADE cosmic ray observatories. After short introduction of the experiment I will present my contribution. My task was to calculate and yields in proton-carbon interactions. The results aim to improve predictions of the neutrino flux in the T2K experiment. The data were recorded in year 2009 using a secondary-proton beam of GeV/ momentum scattered off a graphite target. To determine the inclusive production cross-section for hadrons the thin () target was exploited. Results of this measurement will be used in the T2K beam simulation program to constrain parameters of the neutrino flux
Lambda hyperon production in p+c collisions
Get PDFU radu je određen multiplicitet Λ hiperona u ovisnosti o kutu produkcije i ukupnom impulsu u proton+ugljik sudarima. Podaci su prikupljeni 2009. godine koristeći snop protona impulsa 31 GeV/c te tanku grafitnu metu (0:04 interakcijske duljine). Mjerenja su vršena u okviru NA61/SHINE eksperimenta, velikog hadronskog spektrometara na SPS akceleratorskom postrojenju u CERN-u. Λ hiperoni identificirani su putem nabijenog kanala raspada Λ → p + π. Rezultati su korigirani za geometrijske gubitke, gubitke zbog neefikasnosti rekonstrukcije kao i gubitke zbog primijenjenih rezova korištenjem VENUS Monte Carlo generatora. Ispitana je ovisnost rezultata o rezovima primijenjenim u analizi, Monte Carlo generatoru korištenom pri određivanju korekcijskih faktora te o izboru funkcija korištenih u prilagodbi. Ovisnost produkcije Λ hiperona o laboratorijskom impulsu prikazana je za 7 intervala laboratorijskog polarnog kuta θ (0 - 0:42 rad). Rezultati su uspoređeni s predviđanjima VENUS i FLUKA Monte Carlo generatora te provjereni u neovisnoj analizi. Dobiveni rezultati doprinijeti će preciznijim predviđanju toka neutrina u T2K eksperimentu u Japanu.In this thesis Λ hyperon production in proton-carbon collisions was determined. The data were recorded in year 2009 using a proton beam of 31 GeV/c momentum scattered of a thin graphite target (0:04 interaction length). The measurements were done using NA61/SHINE large hadron spectrometer at SPS accelerator complex at CERN. Λ hyperon was identified via charged decay mode Λ → p + π. Final results are corrected for the losses during the analysis, geometry of the detector and inefficiency of the reconstruction chain using VENUS Monte Carlo simulation. Dependence of the results on cuts, Monte Carlo generator and fitting procedure is investigated. Λ hyperon yields are shown as a function of laboratory momentum in the 7 intervals of laboratory polar angle θ (0 - 0:42 rad). The results are compared to the predictions of VENUS and FLUKA Monte Carlo generators and cross-checked in an independent analysis. The results aim to improve predictions of the neutrino flux in the T2K experiment in Japan
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
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