Application of fuzzy sets in reliability calculation of the oil and gas equipment

Oil and gas equipment, and electric motors in particular, often operate in different duty cycles under changing environmental conditions. The exact effect of these factors on the equipment reliability is rather uncertain. Defining the reliability parameters as fuzzy numbers allows managing such uncertainty. The paper provides an example of fuzzy-valued reliability function estimation. Four-parameter additive Weibull distribution is considered as a reliability model with bathtubshaped failure rate function

A Search for Neutrinos from the Solar hep Reaction and the Diffuse Supernova Neutrino Background with the Sudbury Neutrino Observatory

A search has been made for neutrinos from the hep reaction in the Sun and from the diffus

Independent measurement of the total active B8 solar neutrino flux using an array of He3 proportional counters at the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (νx) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54-0.31+0.33(stat)-0.34+0.36(syst)×106  cm-2 s-1, in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Δm2=7.59-0.21+0.19×10-5  eV2 and θ=34.4-1.2+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO’s previous results

Measurement of the νe\nu_e and Total 8^{8}B Solar Neutrino Fluxes with the Sudbury Neutrino Observatory Phase I Data Set

This article provides the complete description of results from the Phase I data set of the Sudbury Neutrino Observatory (SNO). The Phase I data set is based on a 0.65 kt-year exposure of heavy water to the solar $^8$B neutrino flux. Included here are details of the SNO physics and detector model, evaluations of systematic uncertainties, and estimates of backgrounds. Also discussed are SNO's approach to statistical extraction of the signals from the three neutrino reactions (charged current, neutral current, and elastic scattering) and the results of a search for a day-night asymmetry in the $\nu_e$ flux. Under the assumption that the $^8$B spectrum is undistorted, the measurements from this phase yield a solar $\nu_e$ flux of $\phi(\nu_e) = 1.76^{+0.05}_{-0.05}{(stat.)}^{+0.09}_{-0.09} {(syst.)} \times 10^{6}$ cm$^{-2}$ s$^{-1}$, and a non-$\nu_e$ component $\phi(\nu_{\mu\tau}) = 3.41^{+0.45}_{-0.45}{(stat.)}^{+0.48}_{-0.45} {(syst.)} \times 10^{6}$ cm$^{-2}$ s$^{-1}$. The sum of these components provides a total flux in excellent agreement with the predictions of Standard Solar Models. The day-night asymmetry in the $\nu_e$ flux is found to be $A_{e} = 7.0 \pm 4.9 \mathrm{(stat.)^{+1.3}_{-1.2}}$, when the asymmetry in the total flux is constrained to be zero.Comment: Complete (archival) version of SNO Phase I results. 78 pages, 46 figures, 34 table

Measurement of the νe and total 8B solar neutrino fluxes with the Sudbury Neutrino Observatory phase-III data set

This paper details the solar neutrino analysis of the 385.17-day phase-III data set acquired by the Sudbury Neutrino Observatory (SNO). An array of 3He proportional counters was installed in the heavy-water target to measure precisely the rate of neutrino-deuteron neutral-current interactions. This technique to determine the total active 8B solar neutrino flux was largely independent of the methods employed in previous phases. The total flux of active neutrinos was measured to be 5.54-0.31+0.33(stat.)-0.34+0.36(syst.)×106 cm-2 s-1, consistent with previous measurements and standard solar models. A global analysis of solar and reactor neutrino mixing parameters yielded the best-fit values of Δm2=7.59-0.21+0.19×10 -5eV2 and θ=34.4-1.2+1.3degrees