11,336 research outputs found

    Analytical and Experimental Determination of FML Stiffness and Strength Properties.

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    The paper presents application of analytical methods of determining the mechanical properties of Fibre Metal Laminates. Chosen micromechanical methods were employed to predict elastic moduli and strength of FML panels. Prediction was conducted on two levels i.e. micromechanics where properties of a single composite lamina (prepreg) were analyzed, and macro–mechanics to determine properties of a full FML hybrid material. The properties of a single GFR lamina were predicted by Rule of Mixture Method (ROM), inverse Rule of Mixture Method with correction factor, Halpin Tsai Method, Tsai Method and Wilczynski Method application. Properties of full 3–2 FML lay–up were determined using the Rule of Mixtures. Analytical results were verified by experimental tests. Tensile and bending test were performed on rectangular standard coupons of 3–2 FMLs

    Emerging ΔMd\Delta M_{d}-Anomaly from Tree-Level Determinations of Vcb|V_{cb}| and the Angle γ\gamma

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    We point out that the recently increased value of the angle γ\gamma in the Unitarity Triangle (UT), determined in tree-level decays to be γ=(74.05.8+5.0)\gamma=(74.0^{+5.0}_{-5.8})^\circ by the LHCb collaboration, combined with the most recent value of Vcb|V_{cb}| implies an enhancement of ΔMd\Delta M_{d} over the data in the ballpark of 30%30\%. This is roughly by a factor of two larger than the enhancement of ΔMs\Delta M_{s} that is independent of γ\gamma. This disparity of enhancements is problematic for models with Constrained Minimal Flavour Violation (CMFV) and also for U(2)3U(2)^3 models. In view of the prospects of measuring γ\gamma with the precision of ±1\pm 1^\circ by Belle II and LHCb in the coming years, we propose to use the angles γ\gamma and β\beta together with Vcb|V_{cb}| and Vus|V_{us}| as the fundamental parameters of the CKM matrix until Vub|V_{ub}| from tree-level decays will be known precisely. Displaying ΔMs,d\Delta M_{s,d} as functions of γ\gamma clearly demonstrates the tension between the value of γ\gamma from tree-level decays, free from new physics (NP) contributions, and ΔMs,d\Delta M_{s,d} calculated in CMFV and U(2)3U(2)^3 models and thus exhibits the presence of NP contributions to ΔMs,d\Delta M_{s,d} beyond these frameworks. We calculate the values of Vub|V_{ub}| and Vtd|V_{td}| as functions of γ\gamma and Vcb|V_{cb}| and discuss the implications of our results for εK\varepsilon_K and rare KK and BB decays. We also briefly discuss a future strategy in which β\beta, possibly affected by NP, is replaced by Vub|V_{ub}|.Comment: 15 pages, 8 figures, 3 tables. v2: Clarifying comments and one figure added, conclusions unchanged. Matches published versio

    The chemical compatibility of thermoplastic hose used in umbilicals

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    The effects of solvents and temperature on thermoplastic hose for umbilical service are reported in this paper. Accelerated ageing tests were undertaken and analysed by gravimetric, mechanical and calorimetric measurements. Water and methanol were found to cause physical degradation of the polymer, mainly at high temperatures, whereas xylene caused chemical degradation, which increased with increasing temperature. The activation energy for the alpha-process within polyethylene (PE) was found to be 96.3 kJ mol(-1) for un-aged PE and increased to 106.2 kJ moll after 64 days of ageing in water at 100degreesC. The changes in activation energy will be used to make a life-time prediction of umbilical line

    FCNC Processes in the Littlest Higgs Model with T-Parity: an Update

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    We update our 2006-2007 results for FCNC processes in the Littlest Higgs model with T-parity (LHT). The removal of the logarithmic UV cutoff dependence in our previous results through a new contribution to the Z^0-penguin diagrams identified by Goto et al. and del Aguila et al., while making the deviations from the SM expectations in the quark sector less spectacular, still allows for sizable new physics effects in K -> pi nu anti-nu and K_L -> pi^0 l^+ l^- decays and in the CP-asymmetry S_{psi phi} with the latter unaffected by the new contribution. We extend our analysis by a study of the fine-tuning required to fit the data on epsilon_K and by the inclusion of the decay K_L -> mu^+ mu^-. A number of correlations can distinguish this model from the custodially protected Randall-Sundrum model analysed recently. We also reconsider lepton flavour violating decays, including now a discussion of fine-tuning. While the l_i -> l_j gamma decays are unaffected by the removal of the logarithmic cutoff dependence, the branching ratios for decays with three leptons in the final state, like mu -> 3 e are lowered by almost an order of magnitude. In spite of this, the pattern of lepton flavour violation in the LHT model can still be distinguished from the one in supersymmetric models.Comment: 30 pages, 14 figures, 5 tables. Clarifying comments added, matches published versio
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