87,656 research outputs found

    Exclusive processes in pp collisions in CMS

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    We report the results on the searches of exclusive production of low- and high-mass pairs with the Compact Muon Solenoid (CMS) detector in proton-proton collisions at s\sqrt{s} = 7 TeV. The analyses comprise the central exclusive γγ\gamma\gamma production, the exclusive two-photon production of dileptons, e+e−e^{+}e^{-} and μ+μ−\mu^{+}\mu^{-}, and the exclusive two-photon production of WW pairs in the asymmetric e±μ∓e^{\pm}\mu^{\mp} decay channel. No diphotons candidates are observed in data and an upper limit on the cross section is set to 1.18 pb with 95% confidence level for ET(γ)>E_{T}(\gamma)> 5.5 GeV and ∣η(γ)∣<|\eta(\gamma)|< 2.5. In the measurement of exclusive dilepton production, seventeen e+e−e^{+}e^{-} candidates are observed in data with ET(e)>E_{T}(e)> 5.5 GeV and ∣η(e)∣<|\eta(e)|< 2.5, and the cross section for the exclusive dimuon production is set to σ(pp→p μ+μ− p)=3.38−0.55+0.58\sigma(pp\to p\,\mu^{+}\mu^{-}\,p)=3.38^{+0.58}_{-0.55} (stat.) ±\pm 0.16 (syst.) ±\pm 0.14 (lumi.) pb for m(μ+μ−)>m(\mu^{+}\mu^{-})> 11.5 GeV, pT(μ)>p_{\textrm{T}}(\mu)> 4 GeV and ∣η(μ)∣<|\eta(\mu)|< 2.1, both in agreement with the theoretical predictions. For high-mass systems, two events are observed in data for the exclusive two-photon production of WW pairs for pT(μ)>p_{\textrm{T}}(\mu)> 4 GeV, ∣η(μ)∣|\eta(\mu)| 20 GeV. Moreover, the study of the tail of the dilepton transverse momentum distribution resulted in model-independent upper limits for the anomalous quartic gauge couplings, which are of the order of 10−4^{-4}.Comment: 7 pages, 6 figures, presented at the XXI International Workshop on Deep-Inelastic Scattering and Related Subjects, April 2013, Marseille, Franc

    Sub-Riemannian Ricci curvatures and universal diameter bounds for 3-Sasakian manifolds

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    For a fat sub-Riemannian structure, we introduce three canonical Ricci curvatures in the sense of Agrachev-Zelenko-Li. Under appropriate bounds we prove comparison theorems for conjugate lengths, Bonnet-Myers type results and Laplacian comparison theorems for the intrinsic sub-Laplacian. As an application, we consider the sub-Riemannian structure of 33-Sasakian manifolds, for which we provide explicit curvature formulas. We prove that any complete 33-Sasakian structure of dimension 4d+34d+3, with d>1d>1, has sub-Riemannian diameter bounded by π\pi. When d=1d=1, a similar statement holds under additional Ricci bounds. These results are sharp for the natural sub-Riemannian structure on S4d+3\mathbb{S}^{4d+3} of the quaternionic Hopf fibrations: \begin{equation*} \mathbb{S}^3 \hookrightarrow \mathbb{S}^{4d+3} \to \mathbb{HP}^d, \end{equation*} whose exact sub-Riemannian diameter is π\pi, for all d≥1d \geq 1.Comment: 34 pages, v2: fixed and clarified the proof of Theorem 7 and some typos, v3: final version, to appear on Journal of the Institute of Mathematics of Jussie

    Sustainable machining - correlation of the optimization by minimum energy, minimum manufacturing time and cost of production

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    The machining process leads the indices of productivity and employability in a world level and has an enormous influence at social and economics standards, however it requires machinery that consume high levels of energy, chemical fluids and has great emissions of greenhouse gases. In our days as governments and clients increase their demands for the degradation of ecosystems, also increase the need for companies to implement sustainable policies and improve their environmental performances. The reduction of energy consumption and consequently the reduction of fossil supplies are a major source of concern at this level. This article establish a bridge between the classical approaches of optimization models of machining processes (Maximizing Production Rate and Minimizing Production Cost), and reduction of electricity. For a single pass turning it was used a mathematical model to analyse the data taken as a reference, optimizing the critical parameters of consumption of time, money and energy

    The influence of brand effect on slogan‘s memorability

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    Purpose: The main aim of this article is to examine the influence of consumers’ brand effect on their ability to remember brand slogans. Design/Methodology/Approach: An empirical quantitative study was carried out via an online questionnaire, analyzing 370 real costumers of three telecom B2C service providers in Portugal. Findings: The results tend to indicate to not corroborate the positive influence of brand effect on brand slogan memorability. However, it was also found evidence to raise doubts on the absence of the relationships, since some components of brand effect had a positive impact on slogan recognition in some of the brands studied. Practical implications: Brands might consider focusing on other dimensions besides brand effect, if their aim is to increase brand and slogan awareness. However, since some contradictory results were verified, managers should not view that implication as a golden rule for management and branding decisions. Originality/Value: The main contribution of this study is to shed a light on a relation not yet sufficiently explored in previous studies related to slogan’s effectiveness.peer-reviewe

    Critical analysis of a Musculoskeletal Disorders Prevention Program

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    Critical analysis of a Musculoskeletal Disorders Prevention ProgramThe studies involving the development of occupational diseases and accidents at work prevention programs have delimited two facts. One of them is that the program must be linked to the general organization politics. The other fact is that the diagnosis and the intervention about the organizational culture are necessary for the program to reach its goals. This research have aimed to evaluate an ergonomic intervention called Legislature Court, – Prevention of Musculoskeletal Disorders Program – developed, during one year, at the in Santa Catarina, compounded by 61 work environments. The demand have come from the institution direction, which have noticed the growing rise of Musculoskeletal Disorders. Thus, the direction have hired two professionals from the Ergonomics area (phychologist and physiotherapist) for contributing to the team organization which would be formed by the institutions´employess. The PMDP have initially aimed: to investigate the diseases demand and to evaluate the professionals, able to participate in the multidisciplinary team which would develop the PMDP. The program have gathered diagnosis strategies and interventions highlighted by ergonomics, work psychology and physiotherapy. The strategies were brought in two dimensions: the organizational and the individual. On the individual dimension there were performed physical activities on the work environment, followed by discussions about body conscious, in 14 place of the institution, visitations for understanding the work conditions, followed by discussions about the furniture adequacy and body posture; and three groups of preventive activities. On the organizational dimension it was planned for the multidisciplinary team to integrate the department in charge of the maintenance of the building and the health department. For the critical analysis of the program’s results, the data were collected by: : a) historical rescue of the PMDP; b) surveys with the employees who partipated in the multidisciplinary team; c) questionnaires in a stratified pre-sample of the activities´particpants. The critical analysis of the program´s results, can be initially understood, by the political aspect, due to the fact that the multidisciplinary team was built aiming the self-management, facing the human relations´ institutionalization, which permeates the politics adopted by the Intitution. However, the team didn´t reflect about the politics ´attitude and how it was against the whole organization politics. The team professional project was intervening on the Musculoskeletal Disorders prevention. This made them to be recognized as references on Ergonomics and Health. However, the team wasn´t recognized by the institution’s direction, who didn’t have a commitment with the PMDP. To conclude, the result’s criticism shows the comprehension a team must have about its own politics, about its organization politics and how it can determine a Musculoskeletal Disorders Prevention Program and its limits
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