117,759 research outputs found
Acoustic measurements of Bonci theatre in 2012
No full textThe acoustical quality of an historical theatre may be assessed using the criteria extracted from impulse responses (IRs) measured at listener seats. ISO 3382 recommends a minimal set of positions, but also suggests that increasing the receiver number the accuracy of the measurements increases. The Charter of Ferrara suggests different minimum sets of measurement points in different historical type of theatres. The present study evaluates the accuracy of measurements studying the statistics of the monaural criteria of the reverberation time (T30 and EDT) extracted from IRs.
Measurements of IR have been made in the Bonci
Theatre in Cesena. The Bonci theatre has been
built in the 19th century, is horse-shoe shaped with an
audience, four tier and a gallery. It may already object of
a round robin test of the italian research groups in 2003
[9] and may be assumed an adequate case study of italian
historical theatre
Nonlinear Schrödinger equation and wave function collapse: An unreliable consequence of the semiclassical approximation.
No full textWe consider the spin-boson model as a measurement device, with the 1/2-spin system acting as a pointer and the influence of the environment simulated by means of the interaction between the 1/2-spin system and a dissipative oscillator. In accordance with the recent finding of Bonilla and Guinea [L. L. Bonilla and F. Guinea, Phys. Rev. A 45, 7718 (1992)] the assumption that the oscillator is classical results, under specific conditions, in the occurrence of a wave-function collapse. However, our theoretical analysis shows that the wave-function collapse is provoked by the action exerted by the 1/2-spin system on the oscillator (reaction field) and that the reaction field is as intense as the quantum-mechanical fluctuation neglected by the semiclassical approximation. A numerical treatment shows that no collapse occurs within a fully-quantum-mechanical treatment
Titanium anchors for the repair of distal Achilles tendon ruptures: preliminary report of a new surgical technique
No full textFrom January 1995 to July 1996, the authors used Mitek GIV titanium anchors to treat seven patients with acute rupture of the Achilles tendon (four men, three women; average age 52.42 years; range, 33-62 years). All subjects had a total rupture of the most distal aspect of the tendon; none had an avulsion fracture. After dissection down to the paratenon, the reinsertion site was selected and a 2 to 3-cm-long trough carved through the cortex. Three holes were drilled at a distance of 0.5 cm one from the other and 1 cm parallel and distal to the trough. The anchors were then threaded, inserted into the holes, and engaged. Surgery was completed by resection of the frayed ends, reparation of the tendon, and insertion of the terminal end into the trough. At 6 months postoperative, a modified Mandelbaum and Pavanini clinical assessment indicated five excellent and two good outcomes. There were no cases of deep of superficial wound infection or skin necrosis. Despite the small number of patients and the short follow-up period, the authors believe this technique shows promise and that in selected cases the use of titanium anchors can facilitate the task of the surgeon and enable patients to return to normal and sports activities within 5 months after surgery
BEYOND THE SEMICLASSICAL APPROXIMATION OF THE DISCRETE NONLINEAR SCHRODINGER-EQUATION - COLLAPSES AND REVIVALS AS A SIGN OF QUANTUM FLUCTUATIONS
No full textSpontaneous localizations, environment-induced decoherence and individual-system observations
No full textWe show that the modified version of quantum mechanics proposed by Ghirardi et al. [Phys. Rev. A 40 (1990) 78] is virtually equivalent to ordinary quantum mechanics, if a statistical perspective is adopted. However, this does not conflict with the possibility of an experimental assessment via individual-system observations
Analysis of power dissipation in clocked quantum cellular automaton circuits
No full textWe investigate power dissipation in Quantum Cellular Automaton (QCA) circuits, focusing on the clocked version, and including also the contribution from the nonunitary efficiency of the charging process. The dissipated energy is computed from an integration on the V - Q plane over a complete clock cycle. Results show that power dissipation in a QCA cell, also including the efficiency of the refrigerator needed to cool down the QCA circuit to the operating temperature, appears to be a few orders of magnitude smaller than those typical of traditional technologies. A fairer comparison, however, must take into account also the number of devices that are needed to accomplish a given functionality and the possibility of operating traditional devices with power saving adiabatic schemes
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