260 research outputs found
BFF: A tool for eliciting tie strength and user communities in social networking services
The final publication is available at Springer via http://dx.doi.org/ 10.1007/s10796-013-9453-6The use of social networking services (SNSs) such as Facebook has explosively grown in the last few years. Users see these SNSs as useful tools to find friends and interact with them. Moreover, SNSs allow their users to share photos, videos, and express their thoughts and feelings. However, users are usually concerned about their privacy when using SNSs. This is because the public image of a subject can be affected by photos or comments posted on a social network. In this way, recent studies demonstrate that users are demanding better mechanisms to protect their privacy. An appropriate approximation to solve this could be a privacy assistant software agent that automatically suggests a privacy policy for any item to be shared on a SNS. The first step for developing such an agent is to be able to elicit meaningful information that can lead to accurate privacy policy predictions. In particular, the information needed is user communities and the strength of users' relationships, which, as suggested by recent empirical evidence, are the most important factors that drive disclosure in SNSs. Given the number of friends that users can have and the number of communities they may be involved on, it is infeasible that users are able to provide this information without the whole eliciting process becoming confusing and time consuming. In this work, we present a tool called Best Friend Forever (BFF) that automatically classifies the friends of a user in communities and assigns a value to the strength of the relationship ties to each one. We also present an experimental evaluation involving 38 subjects that showed that BFF can significantly alleviate the burden of eliciting communities and relationship strength.This work has been partially supported by CONSOLIDER-INGENIO 2010 under grant CSD2007-00022, and TIN 2008-04446 and PROMETEO II/2013/019 projects. This article has been developed as a result of a mobility stay funded by the Erasmus Mundus Programme of the European Comission under the Transatlantic Partnership for Excellence in Engineering - TEE Project.López Fogués, R.; Such Aparicio, JM.; Espinosa Minguet, AR.; GarcÃa-Fornes, A. (2014). BFF: A tool for eliciting tie strength and user communities in social networking services. Information Systems Frontiers. 16:225-237. https://doi.org/10.1007/s10796-013-9453-6S22523716Blondel, V.D., Guillaume, J.L., Lambiotte, R., Lefebvre, E. (2008). Fast unfolding of communities in large networks. Journal of Statistical Mechanics: Theory and Experiment, 2008(10), P10008.Boyd, D., & Hargittai, E. (2010). Facebook privacy settings: who cares? First Monday, 15(8).Burt, R. (1995). Structural holes: the social structure of competition. Harvard University Pr.Culotta, A., Bekkerman, R., McCallum, A. (2004). 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The personality of popular facebook users. In Proceedings of the ACM 2012 conference on computer supported cooperative work (CSCW’12).Rosvall, M., & Bergstrom, C. (2008). Maps of random walks on complex networks reveal community structure. Proceedings of the National Academy of Sciences, 105(4), 1118–1123.Sharma, G., Qiang, Y., Wenjun, S., Qi, L. (2013). Communication in virtual world: Second life and business opportunities. Information Systems Frontiers, 15(4), 677–694.Shen, K., Song, L., Yang, X., Zhang, W. (2010). A hierarchical diffusion algorithm for community detection in social networks. In 2010 international conference on cyber-enabled distributed computing and knowledge discovery (CyberC) (pp. 276–283). IEEE.Sierra, C., & Debenham, J. (2007). The LOGIC negotiation model. In AAMAS ’07: proceedings of the 6th international joint conference on autonomous agents and multiagent systems (pp. 1–8). ACM.Staddon, J., Huffaker, D., Brown, L., Sedley, A. (2012). Are privacy concerns a turn-off?: engagement and privacy in social networks. In Proceedings of the eighth symposium on usable privacy and security (p. 10). ACM.Strater, K., & Lipford, H.R. (2008). Strategies and struggles with privacy in an online social networking community. In Proceedings of the 22nd British HCI group annual conference on people and computers: culture, creativity, interaction, BCS-HCI ’08 (Vol. 1, pp. 111–119). Swinton: British Computer Society.Wellman, B., & Wortley, S. (1990). Different strokes from different folks: Community ties and social support. American Journal of Sociology, 558–588.Wiese, J., Kelley, P., Cranor, L., Dabbish, L., Hong, J., Zimmerman, J. (2011). Are you close with me? are you nearby? investigating social groups, closeness, and willingness to share. In Proceedings of the 13th international conference on Ubiquitous computing (pp. 197–206). ACM.Xiang, R., Neville, J., Rogati, M. (2010). Modeling relationship strength in online social networks. 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Decoupling property of the supersymmetric Higgs sector with four doublets
In supersymmetric standard models with multi Higgs doublet fields,
selfcoupling constants in the Higgs potential come only from the D-terms at the
tree level. We investigate the decoupling property of additional two heavier
Higgs doublet fields in the supersymmetric standard model with four Higgs
doublets. In particular, we study how they can modify the predictions on the
quantities well predicted in the minimal supersymmetric standard model (MSSM),
when the extra doublet fields are rather heavy to be measured at collider
experiments. The B-term mixing between these extra heavy Higgs bosons and the
relatively light MSSM-like Higgs bosons can significantly change the
predictions in the MSSM such as on the masses of MSSM-like Higgs bosons as well
as the mixing angle for the two light CP-even scalar states. We first give
formulae for deviations in the observables of the MSSM in the decoupling region
for the extra two doublet fields. We then examine possible deviations in the
Higgs sector numerically, and discuss their phenomenological implications.Comment: 26 pages, 24 figures, text sligtly modified,version to appear in
Journal of High Energy Physic
Uso da acupressão para minimizar desconfortos na gestação
Objetivo: Descrever respostas emitidas por gestantes, quanto à melhora dos desconfortos gravÃdicos após aplicação da técnica da acupressão.Método: Estudo qualitativo e descritivo desenvolvido com 15 gestantes entre novembro de 2013 e fevereiro de 2014 em uma Unidade Básica de Saúde de Natal-RN, Brasil. A coleta de dados ocorreu por meio de entrevista não estruturada, e os depoimentos, depois de transcritos e tratados de acordo com a proposta operativa de Minayo, foram lidos criteriosamente, comparados entre si e organizados em dois grupos.Resultados: As categorias suscitadas foram: Repercussões positivas da acupressão e Recomendações do uso da acupressão. Segundo as gestantes, os desconfortos da gravidez como câimbras, cansaço nos membros inferiores, lombalgia e cefaleia diminuÃram com o uso da acupressão.Conclusões: Baseado nos resultados obtidos, a acupressão deve ser introduzida pela(o) enfermeira(o) em consultas pré-natais como recurso terapêutico em prol da obtenção do bem-estar da gestante.Palavras-chave: Enfermagem obstétrica. Cuidado pré-natal. Acupressão. Humanização da assistência
Composite Higgs Search at the LHC
The Higgs boson production cross-sections and decay rates depend, within the
Standard Model (SM), on a single unknown parameter, the Higgs mass. In
composite Higgs models where the Higgs boson emerges as a pseudo-Goldstone
boson from a strongly-interacting sector, additional parameters control the
Higgs properties which then deviate from the SM ones. These deviations modify
the LEP and Tevatron exclusion bounds and significantly affect the searches for
the Higgs boson at the LHC. In some cases, all the Higgs couplings are reduced,
which results in deterioration of the Higgs searches but the deviations of the
Higgs couplings can also allow for an enhancement of the gluon-fusion
production channel, leading to higher statistical significances. The search in
the H to gamma gamma channel can also be substantially improved due to an
enhancement of the branching fraction for the decay of the Higgs boson into a
pair of photons.Comment: 32 pages, 16 figure
Validity and reliability of the Foot Function Index (FFI) questionnaire Brazilian-Portuguese version
Phenomenology of the Higgs effective Lagrangian via FeynRules
The Higgs discovery and the lack of any other hint for new physics favor a description of non-standard Higgs physics in terms of an effective field theory. We present an implementation of a general Higgs effective Lagrangian containing operators up to dimension six in the framework of FeynRules and provide details on the translation between the mass and interaction bases, in particular for three- and four-point interaction vertices involving Higgs and gauge bosons. We illustrate the strengths of this implementation by using the UFO interface of FeynRules capable to generate model files that can be understood by the MadGraph 5 event generator and that have the specificity to contain all interaction vertices, without any restriction on the number of external legs or on the complexity of the Lorentz structures. We then investigate several new physics effects in total rates and differential distributions for different Higgs production modes, including gluon fusion, associated production with a gauge boson and di-Higgs production. We finally study contact interactions of gauge and Higgs bosons to fermions
Composite Higgs Boson Pair Production at the LHC
The measurement of the trilinear and quartic Higgs self-couplings is
necessary for the reconstruction of the Higgs potential. This way the Higgs
mechanism as the origin of electroweak symmetry breaking can be tested. The
couplings are accessible in multi-Higgs production processes at the LHC. In
this paper we investigate the prospects of measuring the trilinear Higgs
coupling in composite Higgs models. In these models, the Higgs boson emerges as
a pseudo-Goldstone boson of a strongly interacting sector, and the Higgs
potential is generated by loops of the Standard Model (SM) gauge bosons and
fermions. The Higgs self-couplings are modified compared to the SM and
controlled by the compositeness parameter in addition to the Higgs boson
mass. We construct areas of sensitivity to the trilinear Higgs coupling in the
relevant parameter space for various final states
Higgs boson masses and mixings in the complex MSSM with two-loop top-Yukawa-coupling corrections
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe
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