1,720,970 research outputs found
Kaon CP violation and neutron EDM in the minimal left-right symmetric model
No full textWithin the minimal left-right (LR) symmetric model we revisit the predictions for the kaon CP violating observables Ï and Ï′ in correlation with the neutron electric dipole moment. We perform a complete study of the cross constraints on the model parameters, phases and the MWR scale, considering the two cases of extended parity or charge conjugation as LR discrete symmetries, together with the possible presence of a Peccei-Quinn symmetry. We discuss in particular two scenarios: Whether the Standard Model saturates the experimental value of Ï′/Ï or whether new physics is needed, still an open issue after the recent lattice results on the QCD penguin matrix elements. Within the first scenario, we find no constraints on the LR scale in the charge-conjugation case while in the parity case we show that MWR can be as low as 13 TeV. On the other side, the request that new physics contributes dominantly to Ï′ implies strong correlations among the model parameters, with an upper bound of MWR<8-100 TeV depending on tanβ in the case of charge conjugation and a range of MWR≃7-45 TeV in the parity setup. Both scenarios may be probed directly at future colliders and only indirectly at the LHC
New physics in ε′ from gluomagnetic contributions and limits on Left-Right symmetry
No full textNew physics in the chromomagnetic flavor changing transition s ! dg0 can avoid the strong Glashow- Iliopoulos-Maiani suppression of the standard model and lead to large contributions to CP-violating observables, in particular to the 0 parameter, that we address here. We discuss the case of the left-right symmetric models, where this contribution implies bounds on the phases of the right-handed quark mixing matrix, or in generic models with large phases a strong bound on the left-right symmetry scale. To the leading order, a numeric formula for 0 as a function of the short-distance coefficients for a wide class of models of new physics is given.New physics in the chromomagnetic flavor changing transition s→dg∗ can avoid the strong Glashow-Iliopoulos-Maiani suppression of the standard model and lead to large contributions to CP-violating observables, in particular to the ε′ parameter, that we address here. We discuss the case of the left-right symmetric models, where this contribution implies bounds on the phases of the right-handed quark mixing matrix, or in generic models with large phases a strong bound on the left-right symmetry scale. To the leading order, a numeric formula for ε′ as a function of the short-distance coefficients for a wide class of models of new physics is given
Left-right symmetry at LHC
No full textWe revisit the issue of the limit on the scale of left-right symmetry breaking. We focus on the minimal SUð2ÞL SUð2ÞR Uð1ÞBL gauge theory with the seesaw mechanism and discuss the two possibilities of defining left-right symmetry as parity or charge conjugation. In the commonly adopted case of parity, we perform a complete numerical study of the quark mass matrices and the associated left and right mixing matrices without any assumptions usually made in the literature about the ratio of vacuum expectation values. We find that the usual lower limit on the mass of the right-handed gauge boson from the K mass difference, MWR > 2:5 TeV, is subject to a possible small reduction due to the difference between right and left Cabibbo angles. In the case of charge conjugation the limit on MWR is somewhat more robust. However, the more severe bounds from CP-violating observables are absent in this case. In fact, the free phases can also resolve the present mild discrepancy between the standard model and CP violation in the B sector. Thus, even in the minimal case, both charged and neutral gauge bosons may be accessible at the Large Hadron Collider with spectacular signatures of lepton number violation.We revisit the issue of the limit on the scale of left-right symmetry breaking. We focus on the minimal SU(2)(L) x SU(2)(R) x U(1)(B-L) gauge theory with the seesaw mechanism and discuss the two possibilities of defining left-right symmetry as parity or charge conjugation. In the commonly adopted case of parity, we perform a complete numerical study of the quark mass matrices and the associated left and right mixing matrices without any assumptions usually made in the literature about the ratio of vacuum expectation values. We find that the usual lower limit on the mass of the right-handed gauge boson from the K mass difference, M(WR) > 2.5 TeV, is subject to a possible small reduction due to the difference between right and left Cabibbo angles. In the case of charge conjugation the limit on M(WR) is somewhat more robust. However, the more severe bounds from CP-violating observables are absent in this case. In fact, the free phases can also resolve the present mild discrepancy between the standard model and CP violation in the B sector. Thus, even in the minimal case, both charged and neutral gauge bosons may be accessible at the Large Hadron Collider with spectacular signatures of lepton number violation
Scan-to-BIM for architectural heritage enhancement and preservation. Leading techniques and advanced automation processes
Full text linkThe digitisation of Architectural Heritage emerges as a pivotal and groundbreaking
practice crucial for the preservation and enhancement of cultural assets.
This significance becomes particularly pronounced in an era marked by profound
transformations and challenges across multiple fields.
By cutting-edge technologies within a scenario dominated by Artificial Intelligence,
which disrupts established paradigms and approaches, this initiative aims to address
the inherent challenges of long-term conservation. Simultaneously, it aspires to
achieve the broader objective of ensuring enhanced access and a more enriched experience
of historical monuments for both current and future generations, thereby
safeguarding their unique identities.
Heritage's vulnerability must be carefully weighed to strike a delicate balance between
accessibility and contemporary interpretation on the one hand, and authenticity and
integrity on the other. The hazards of digitisation, including the potential loss of stored
information or intentional obsolescence, are closely related to this susceptibility as
well as physical material modifications.
The present thesis, born out of these critical considerations, adopts comprehensive
and multidisciplinary approaches to delve into diverse themes converging within the
realm of architectural survey and drawing for heritage virtualisation.
Through extensive field research conducted in both Italy and Spain, the combined
methodologies of various surveying techniques and technologies, including LiDAR
and Photogrammetry, are thoroughly examined as foundational elements for the digital
acquisition of historical monuments. The resulting data, presented as point clouds,
images, and/or polygonal models, undergo a detailed processing and optimisation
phase employing semi-automatic procedures.
These procedures, primarily focusing on the semantic enrichment of architectural and
structural components, are geared towards facilitating an in-depth analysis of the
conservation status of the monument. This, in turn, translates into improved information management, providing crucial
support for subsequent phases involved in constructing the replicated model of the
architectural masterpiece.
Moving beyond the survey activity, the investigation advances towards Heritage Building
Information Modelling (HBIM) through the adoption of a Scan to BIM approach.
The latter is seamlessly integrated into a unified protocol, streamlining data processing
while ensuring adherence to health and safety regulations for the operator.
This methodology enables a thorough analysis and faithful digitisation of the reproduced
case studies, leveraging metric and geometric references guaranteed by the instrumentation
used, as well as semantic segmentation and classification of data derived
from the automations.
The proposed processes of automation, designed to accelerate processing times,
control operational costs, and enhance the precision and accuracy of results, are meticulously
crafted. Simultaneously, due consideration is given to the experience and
expertise of the operator involved in the activities, ensuring a thoughtful and conscious
approach throughout all stages of the process
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
The Cooperation Human-Machine : educating for creativity in the AI Age
No full textThis article’s aim is to start a reflection on how creativity can be educated with AI. The starting point is the concept of creativity and the synthetic reconstruction of the history of its relationship with technology. On this basis, we go further analyzing the relationship between AI and creativity, before indicating a possible work path for education. The conclusions concern the role of the author and creative production
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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