1,722,263 research outputs found
Soft QCD and pA physics, with a focus on the ridge at LHCb
No full textThe LHCb experiment is a forward spectrometer originally designed for study of b and c hadron decays. However, it can be used in a much wider spectrum of physics analyses. The poster presented here highlights a few studies from the extensive range of soft QCD and heavy-ion physics analyses performed at the LHCb. A particular emphasis is placed on the observation of the two-particle angular correlations, so-called ridge effect, in the forward region. The results presented here serve as one of numerous examples of LHCb being a proven multi-purpose detector in the forward region
Measurement of particle multiplicity and energy flow in pp collisions at 13 TeV with the LHCb detector
No full textThe LHC is the world's largest and highest-energy particle collider. The LHCb experiment is one of four main experiments at the LHC. In July/August 2015, at the beginning of Run-II of the collider, the LHCb detector collected no-bias data during the so-called `Early Measurements' low intensity data taking run. The analysis described in this thesis, the measurement of particle multiplicity and energy flow in proton-proton collisions at a centre-of-mass energy of = 13 TeV, uses this dataset. This analysis is aimed at improving our understanding of the hadron-hadron interaction process in full and, more specifically, our knowledge of the contributions of the underlying event and multi-parton interactions to the observable final states. The data sample is split into the charged and neutral components and then further segregated into four event classes - inclusive minimum-bias, hard scattering, diffractive enriched and non-diffractive enriched. The measurement is carried out over a 2D space within the fiducial acceptance of GeV/c and 2.0 5.0 and a full detector unfolding is performed. The results are presented as 1D multiplicity and energy flow distributions as a function of and compared to four sets of theoretical predictions - Pythia 8 LHCb, Pythia 8 Monash 2013, EPOS LHC and Sibyll 2.1. It is found that the LHCb tune of the Pythia 8.212 generator is able to describe the data the best, whilst the worst performing set of theoretical predictions is found to be EPOS LHC. Overall, the description of the inclusive minimum-bias and non-diffractive enriched event classes by Pythia 8.212 LHCb for both the multiplicity and energy flow is found to match the data well, while the theoretical predictions overestimate the charged component's multiplicity for the diffractive enriched event class and underestimate the neutral multiplicity for the neutral hard scattering event class
Electrical Resistivity Tomography (ERT) and electromagnetic (CMD) assessment of Scottish reservoir embankments
No full textFlood reservoir embankments are playing a very important role during the flood season as they keep the water within the reservoir. The reason for flood reservoir embankment failure is the desiccation of clay fill materials during the dry seasons which cause the fissuring of the top clay layers that could lead to erosion and slip surface with overtopping water. In most cases the failure of flood embankments causes flooding risk to local areas and puts inhabitants at risk. For this reason it is important to investigate the condition of the embankments and evaluate any internal erosion and cracking. These investigations allow greater learning about the soil layers and detection of metallic objects in the ground, animal burials and the vertical fissuring network which are other factors of weakness. The data can also be used to identify high and low conductivity areas related to the moisture of the soil. This report discusses the flood catchment embankment tests using two non-destructive geo-physical testing methods at various sites in East Ayrshire and Renfrewshire, Scotland. The embankments investigations were carried out using CMD (Electromagnetic Conductivity Meter) and ERT (Electrical Resistivity Tomography). The tests identified metal objects (pipes and drains) in various locations on site. These findings were confirmed by visual inspections. Results also revealed that the soil is highly conductive (low resistivity) so no cracking was observed as cracking and cavities are spotted by high resistivity. The upper layer of the embankments sometimes showed signs of desiccation and drier soil. Zones of high conductivity (higher water content) were also identified and the influence of the morphology of the embankments was discussed.Flood reservoir embankments are playing a very important role during the flood season as they keep the water within the reservoir. The reason for flood reservoir embankment failure is the desiccation of clay fill materials during the dry seasons which cause the fissuring of the top clay layers that could lead to erosion and slip surface with overtopping water. In most cases the failure of flood embankments causes flooding risk to local areas and puts inhabitants at risk. For this reason it is important to investigate the condition of the embankments and evaluate any internal erosion and cracking. These investigations allow greater learning about the soil layers and detection of metallic objects in the ground, animal burials and the vertical fissuring network which are other factors of weakness. The data can also be used to identify high and low conductivity areas related to the moisture of the soil. This report discusses the flood catchment embankment tests using two non-destructive geo-physical testing methods at various sites in East Ayrshire and Renfrewshire, Scotland. The embankments investigations were carried out using CMD (Electromagnetic Conductivity Meter) and ERT (Electrical Resistivity Tomography). The tests identified metal objects (pipes and drains) in various locations on site. These findings were confirmed by visual inspections. Results also revealed that the soil is highly conductive (low resistivity) so no cracking was observed as cracking and cavities are spotted by high resistivity. The upper layer of the embankments sometimes showed signs of desiccation and drier soil. Zones of high conductivity (higher water content) were also identified and the influence of the morphology of the embankments was discussed
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
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
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