95 research outputs found

    First order phase transition in the Quantum Adiabatic Algorithm

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    We simulate the quantum adiabatic algorithm (QAA) for the exact cover problem for sizes up to N=256 using quantum Monte Carlo simulations incorporating parallel tempering. At large N we find that some instances have a discontinuous (first order) quantum phase transition during the evolution of the QAA. This fraction increases with increasing N and may tend to 1 for N -> infinity.Comment: 5 pages, 3 figures. Replaced with published version; two figures slightly changed and some small changes to the tex

    Solution to Satisfiability problem by a complete Grover search with trapped ions

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    The main idea in the original Grover search (Phys. Rev. Lett. 79, 325 (1997)) is to single out a target state containing the solution to a search problem by amplifying the amplitude of the state, following the Oracle's job, i.e., a black box giving us information about the target state. We design quantum circuits to accomplish a complete Grover search involving both the Oracle's job and the amplification of the target state, which are employed to solve Satisfiability (SAT) problems. We explore how to carry out the quantum circuits by currently available ion-trap quantum computing technology.Comment: 14 pages, 6 figure

    Experimental research of turbo-codes application in telemedicine systems with wireless body area sensor networks

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    The paper shows telemedicine system with wireless body area sensor networks as a potential technology to provide extremely high quality and convenience for people.We discuss a communication process unit with turbo-codec, that can work with necessary requirements, such as extremely low signal power and high reliability of data transmission. also, the turbo-encoding and decoding math is briefly overviewed. the simulation of turbo-codec work in these networks is shown. experimental functions of bit error rate are found.W artykule przedstawiono system telemedyczny z bezprzewodowyą siecią czujników umieszczaną w obszarze ciała jako potencjalną technologię, która ma zapewnić wyjątkowo wysoką jakość i wygodę dla ludzi. Przedstawiony proces komunikacyjny może pracować przy wymaganiach tj. wyjątkowo niska moc sygnału i wysoka niezawodność transmisji danych. (Eksperymentalne badania zastosowań turbo-kodów w systemach telemedycznych z bezprzewodowymi sieciami czujników ciała)

    Low computational complexity algorithm for recognition highly corrupted QR codes based on Hamming-Lippmann neural network

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    This article describes the architecture of the Hamming-Lippmann neural network and the math of the modified learning-recognition algorithm and presents some practical aspects for using it for solving an image recognition task. We have created software using C# programming language, that utilized this network as an additional error-correcting procedure, and have solved the task of recognition highly corrupted QR codes (with a connection to the database). Experimental results, of finding the optimal parameters for this algorithm, are presented. This neural network doesn’t require time-consuming computational procedures and large amounts of memory, even for high-resolution and big size images.W tym artykule opisano architekturę sieci neuronowej Hamminga-Lippmanna oraz matematykę zmodyfikowanego algorytmu rozpoznawania uczenia się, a także przedstawiono kilka praktycznych aspektów korzystania z niej w celu rozwiązania zadania rozpoznawania obrazu. Stworzyliśmy oprogramowanie wykorzystujące język programowania C #, który wykorzystał tę sieć jako dodatkową procedurę korekty błędów i rozwiązaliśmy zadanie rozpoznawania wysoce uszkodzonych kodów QR (w połączeniu z bazą danych). Przedstawiono wyniki eksperymentalne poszukiwania optymalnych parametrów dla tego algorytmu. Opisywana neuronowa nie wymaga czasochłonnych procedur obliczeniowych i dużej ilości pamięci, nawet w przypadku obrazów o wysokiej rozdzielczości i dużych rozmiarach. (Algorytm o niskiej złożoności obliczeniowej do rozpoznawania wysoce uszkodzonych kodów QR w oparciu o sieć neuronową Hamminga-Lippmanna)

    Случай первого в России применения устройства вспомогательного кровообращения PulseCath iVAC 2L при чрескожном коронарном вмешательстве высокого риска

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    Percutaneous left ventricular assist devices are necessary to maintain blood circulation in patients with cardiogenic shock after high risk percutaneous coronary interventions. The PulseCath iVAC 2L is a new device that can be implanted percutaneously via the femoral artery. The device consists of an extracorporeal membrane pump and a catheter, which is inserted into the left ventricle through the aorta. The pump is connected to the console of the intra-aortic balloon counterpulsator generating a pulsatile blood flow.Чрескожные механические вспомогательные устройства левого желудочка необходимы для поддержания кровообращения во время кардиогенного шока и чрескожных коронарных вмешательств высокого риска. iVAC 2L (PulseCath BV, Нидерланды) – новое устройство, которое можно имплантировать пункционно через бедренную артерию. Система iVAC 2L состоит из экстракорпорального мембранного насоса и катетера, который устанавливается в полость левого желудочка через аорту. Насос подключается к консоли внутриаортального баллонного контрпульсатора, который создает пульсирующий кровоток. В статье приведен клинический случай первого успешного применения в России устройства iVAC 2L при чрескожном коронарном вмешательстве у пациента высокого риска

    Determination of Vub|V_{ub}| from untagged B0π+νB^0\to\pi^- \ell^+ \nu_{\ell} decays using 2019-2021 Belle II data

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    We present an analysis of the charmless semileptonic decay B0π+νB^0\to\pi^- \ell^+ \nu_{\ell}, where =e,μ\ell = e, \mu, from 198.0 million pairs of BBˉB\bar{B} mesons recorded by the Belle II detector at the SuperKEKB electron-positron collider. The decay is reconstructed without identifying the partner BB meson. The partial branching fractions are measured independently for B0πe+νeB^0\to\pi^- e^+ \nu_{e} and B0πμ+νμB^0\to\pi^- \mu^+ \nu_{\mu} as functions of q2q^{2} (momentum transfer squared), using 3896 B0πe+νeB^0\to\pi^- e^+ \nu_{e} and 5466 B0πμ+νμB^0\to\pi^- \mu^+ \nu_{\mu} decays. The total branching fraction is found to be (1.426±0.056±0.125)×104(1.426 \pm 0.056 \pm 0.125) \times 10^{-4} for B0π+νB^0\to\pi^- \ell^+ \nu_{\ell} decays, where the uncertainties are statistical and systematic, respectively. By fitting the measured partial branching fractions as functions of q2q^{2}, together with constraints on the nonperturbative hadronic contribution from lattice QCD calculations, the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element VubV_{ub}, (3.55±0.12±0.13±0.17)×103(3.55 \pm 0.12 \pm 0.13 \pm 0.17) \times 10^{-3}, is extracted. Here, the first uncertainty is statistical, the second is systematic and the third is theoretical

    Angular analysis of B+ρ+ρ0B^+ \to \rho^+\rho^0 decays reconstructed in 2019, 2020, and 2021 Belle II data

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    We report on a Belle II measurement of the branching fraction (B\mathcal{B}), longitudinal polarization fraction (fLf_L), and CP asymmetry (ACP\mathcal{A}_{CP}) of B+ρ+ρ0B^+\to \rho^+\rho^0 decays. We reconstruct B+ρ+(π+π0(γγ))ρ0(π+π)B^+\to \rho^+(\to \pi^+\pi^0(\to \gamma\gamma))\rho^0(\to \pi^+\pi^-) decays in a sample of SuperKEKB electron-positron collisions collected by the Belle II experiment in 2019, 2020, and 2021 at the Υ\Upsilon(4S) resonance and corresponding to 190 fb1^{-1} of integrated luminosity. We fit the distributions of the difference between expected and observed BB candidate energy, continuum-suppression discriminant, dipion masses, and decay angles of the selected samples, to determine a signal yield of 345±31345 \pm 31 events. The signal yields are corrected for efficiencies determined from simulation and control data samples to obtain $\mathcal{B}(B^+ \to \rho^+\rho^0) = [23.2^{+\ 2.2}_{-\ 2.1} (\rm stat) \pm 2.7 (\rm syst)]\times 10^{-6},, f_L = 0.943 ^{+\ 0.035}_{-\ 0.033} (\rm stat)\pm 0.027(\rm syst),and, and \mathcal{A}_{CP}=-0.069 \pm 0.068(\rm stat) \pm 0.060 (\rm syst).Theresultsagreewithpreviousmeasurements.Thisisthefirstmeasurementof. The results agree with previous measurements. This is the first measurement of \mathcal{A}_{CP}in in B^+\to \rho^+\rho^0$ decays reported by Belle II

    Measurement of the branching fraction for the decay BK(892)+B \to K^{\ast}(892)\ell^+\ell^- at Belle II

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    We report a measurement of the branching fraction of BK(892)+B \to K^{\ast}(892)\ell^+\ell^- decays, where +=μ+μ\ell^+\ell^- = \mu^+\mu^- or e+ee^+e^-, using electron-positron collisions recorded at an energy at or near the Υ(4S)\Upsilon(4S) mass and corresponding to an integrated luminosity of 189189 fb1^{-1}. The data was collected during 2019--2021 by the Belle II experiment at the SuperKEKB e+ee^{+}e^{-} asymmetric-energy collider. We reconstruct K(892)K^{\ast}(892) candidates in the K+πK^+\pi^-, KS0π+K_{S}^{0}\pi^+, and K+π0K^+\pi^0 final states. The signal yields with statistical uncertainties are 22±622\pm 6, 18±618 \pm 6, and 38±938 \pm 9 for the decays BK(892)μ+μB \to K^{\ast}(892)\mu^+\mu^-, BK(892)e+eB \to K^{\ast}(892)e^+e^-, and BK(892)+B \to K^{\ast}(892)\ell^+\ell^-, respectively. We measure the branching fractions of these decays for the entire range of the dilepton mass, excluding the very low mass region to suppress the BK(892)γ(e+e)B \to K^{\ast}(892)\gamma(\to e^+e^-) background and regions compatible with decays of charmonium resonances, to be \begin{equation} {\cal B}(B \to K^{\ast}(892)\mu^+\mu^-) = (1.19 \pm 0.31 ^{+0.08}_{-0.07}) \times 10^{-6}, {\cal B}(B \to K^{\ast}(892)e^+e^-) = (1.42 \pm 0.48 \pm 0.09)\times 10^{-6}, {\cal B}(B \to K^{\ast}(892)\ell^+\ell^-) = (1.25 \pm 0.30 ^{+0.08}_{-0.07}) \times 10^{-6}, \end{equation} where the first and second uncertainties are statistical and systematic, respectively. These results, limited by sample size, are the first measurements of BK(892)+B \to K^{\ast}(892)\ell^+\ell^- branching fractions from the Belle II experiment
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