2,710 research outputs found

    Quantum variational measurement in the next generation gravitational-wave detectors

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    A relatively simple method of overcoming the Standard Quantum Limit in the next-generation Advanced LIGO gravitational wave detector is considered. It is based on the quantum variational measurement with a single short (a few tens of meters) filter cavity. Estimates show that this method allows to reduce the radiation pressure noise at low frequencies (<100Hz<100 \mathrm{Hz}) to the level comparable with or smaller than the low-frequency noises of non-quantum origin (mirrors suspension noise, mirrors internal thermal noise, and gravity gradients fluctuations).Comment: 12 pages, 4 figures; NSNS SNR estimates added; misprints correcte

    Investigation of overhang effect on cutting tool vibration for tool condition monitoring

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    Vibration measurement is one of the most widely used indirect methods of tool condition monitring, but vibration signal features may be affected by overhang lenght. In turning process, it is known that for the best overall machining results, tool overhang should be kept to a minimum. However, a longer tool overhang may be required depending on the geometry of the workpiece and in situations such as internal turning process. The long overhang increases vibration. In this paper the relations between tool overhang and the most commonly used signal features is investigated

    Effects of an induced three-body force in the incident channel of (d,p) reactions

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    A widely accepted practice for treating deuteron breakup in A(d,p)BA(d,p)B reactions relies on solving a three-body A+n+pA+n+p Schr\"odinger equation with pairwise AA-nn, AA-pp and nn-pp interactions. However, it was shown in [Phys. Rev. C \textbf{89}, 024605 (2014)] that projection of the many-body A+2A+2 wave function into the three-body A+n+pA+n+p channel results in a complicated three-body operator that cannot be reduced to a sum of pairwise potentials. It contains explicit contributions from terms that include interactions between the neutron and proton via excitation of the target AA. Such terms are normally neglected. We estimate the first order contribution of these induced three-body terms and show that applying the adiabatic approximation to solving the A+n+pA+n+p model results in a simple modification of the two-body nucleon optical potentials. We illustrate the role of these terms for the case of 40^{40}Ca(d,pd,p)41^{41}Ca transfer reactions at incident deuteron energies of 11.8, 20 and 56 MeV, using several parameterisations of nonlocal optical potentials.Comment: 7 pages, 2 figures. Publication due in Phys. Rev.

    Optimal configurations of filter cavity in future gravitational-wave detectors

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    Sensitivity of future laser interferometric gravitational-wave detectors can be improved using squeezed light with frequency-dependent squeeze angle and/or amplitude, which can be created using additional so-called filter cavities. Here we compare performances of several variants of this scheme, proposed during last years, assuming the case of a single relatively short (tens of meters) filter cavity suitable for implementation already during the life cycle of the second generation detectors, like Advanced LIGO. Using numerical optimization, we show that the phase filtering scheme proposed by Kimble et al [Phys.Rev.D 65, 022002 (2001)] looks as the best candidate for this scenario.Comment: 17 pages, 5 figure

    Fuzzy containers allocation problem in maritime terminal

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    Containers allocation in terminals has attracted lots of research works due to practical & theoretical importance in transportation literature. In this paper, we developed a fuzzy mathematical programming model for solving problem of allocating the containers in terminal area. The objective is minimizing the total distance traversed by the containers from the ship to the terminal area they are assigned. Fuzzy set concepts are used to treat imprecision regarding the distances between berth and terminals area, number of containers in an arrived ship and estimation of available area in each terminal at a port. We proposed two types of models for optimistic and pessimistic situations. The proposed models have been coded in LINGO8.0 solver and a numerical example has been solved for illustration purpose. The full analysis of the proposed models can cause an optimum allocation of containers of several ships to different terminals of berths in fuzzy environment.Peer Reviewe
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