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1.
We estimate the quantum state of a qubit and a quantized radiation field yielding a generalized negative binomial distribution (GNBD). We give an explicit form for various generalized negative binomial states associated to superposition, even, odd, and q-deformed states. We investigate the dynamical properties of the Mandel parameter as a quantifier of the statistical properties for the radiation field corresponding to its dynamics. We obtain the quantum Fisher information based on the estimation of the atomic state and compare it with the Mandel parameter for different instances of the GNBD. The link between the statistical quantities for different parameters of the GNBD is explored.  相似文献   
2.
The security of information is necessary for the success of any system. So, there is a need to have a robust mechanism to ensure the verification of any person before allowing him to access the stored data. So, for purposes of increasing the security level and privacy of users against attacks, cancelable biometrics can be utilized. The principal objective of cancelable biometrics is to generate new distorted biometric templates to be stored in biometric databases instead of the original ones. This paper presents effective methods based on different discrete transforms, such as Discrete Fourier Transform (DFT), Fractional Fourier Transform (FrFT), Discrete Cosine Transform (DCT), and Discrete Wavelet Transform (DWT), in addition to matrix rotation to generate cancelable biometric templates, in order to meet revocability and prevent the restoration of the original templates from the generated cancelable ones. Rotated versions of the images are generated in either spatial or transform domains and added together to eliminate the ability to recover the original biometric templates. The cancelability performance is evaluated and tested through extensive simulation results for all proposed methods on a different face and fingerprint datasets. Low Equal Error Rate (EER) values with high AROC values reflect the efficiency of the proposed methods, especially those dependent on DCT and DFrFT. Moreover, a comparative study is performed to evaluate the proposed method with all transformations to select the best one from the security perspective. Furthermore, a comparative analysis is carried out to test the performance of the proposed schemes with the existing schemes. The obtained outcomes reveal the efficiency of the proposed cancelable biometric schemes by introducing an average AROC of 0.998, EER of 0.0023, FAR of 0.008, and FRR of 0.003.  相似文献   
3.
Research on Chemical Intermediates - Zinc oxide-doped tin dioxide (ZnO–SnO2) nanomaterials were prepared by a sol–gel method with and without different amounts (0.5, 1.0 and...  相似文献   
4.

We numerically simulate quantum coherence in a system of two qubits interacting with a reservoir for non-Markovian channels. The explicit form of the master equation is taken in terms of density-operator elements and is solved according to the initial conditions. In particular, we consider the effect of an Ohmic reservoir (OR) with Lorentz–Drude regularization (LDR) on the extent of coherence during dynamics. We describe the dynamical behavior of the coherence for low, intermediate, and high-temperature reservoirs. We explain the effect of the ratio of the cutoff frequency (CF) to the quantum system frequency and the effect of temperature on the quantum coherence. We show that a decreasing ratio enhances coherence, while an increasing temperature decreases it.

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5.
Based on a pseudopotential approach under the virtual crystal approximation, the elastic modulus of InxAl1???xAsySb1???y quaternaries lattice-matched to InP, GaSb and InAs substrates has been investigated. Our findings show a reasonably good accord with experiment. The dependence of the elastic features of interest on the indium concentration x shows a monotonic behaviour when InxAl1???xAsySb1???y is lattice-matched to InP substrate. In that case, the elastic constants have larger values and the material system of interest becomes less harder and its rigidity becomes weaker. The mechanical stability criteria is verified in terms of elastic constants and shows that InxAl1???xAsySb1???y is mechanically stable for each x and substrate being considered here. The change in indium content x and the substrate is found to have no much effect on both the Poisson ratio and machinability. The present study showed that a proper choice of the indium composition x and substrate may provide more diverse opportunities as regards the elastic modulus of InxAl1???xAsySb1???y.  相似文献   
6.
Dynamic cumulative residual (DCR) entropy is a valuable randomness metric that may be used in survival analysis. The Bayesian estimator of the DCR Rényi entropy (DCRRéE) for the Lindley distribution using the gamma prior is discussed in this article. Using a number of selective loss functions, the Bayesian estimator and the Bayesian credible interval are calculated. In order to compare the theoretical results, a Monte Carlo simulation experiment is proposed. Generally, we note that for a small true value of the DCRRéE, the Bayesian estimates under the linear exponential loss function are favorable compared to the others based on this simulation study. Furthermore, for large true values of the DCRRéE, the Bayesian estimate under the precautionary loss function is more suitable than the others. The Bayesian estimates of the DCRRéE work well when increasing the sample size. Real-world data is evaluated for further clarification, allowing the theoretical results to be validated.  相似文献   
7.
Bourchak  M.  Juhany  K. A.  Salah  N.  Ajaj  R.  Algarni  A.  Scarpa  F. 《Mechanics of Composite Materials》2020,56(2):215-226
Mechanics of Composite Materials - In this work, transmission electron microscopy (TEM) and Raman spectroscopy were used to assess the dispersion quality of carbon nanotubes (CNTs) in an epoxy...  相似文献   
8.
Journal of Solid State Electrochemistry - In this study, an MoS2/graphene composite is fabricated from bulk MoS2 and graphite rod via a facile electrochemical exfoliation method. The as-prepared...  相似文献   
9.
Rare earth element (i.e.) europium co-doped aluminum zinc oxide (Eu:AZO) thin films were deposited on microscope glass slides by nebulizer spray pyrolysis with different Eu-doping concentrations (0, 0.5, 1, and 1.5%). The deposited films were investigated using X-ray diffraction, AFM, EDAX, FT-Raman, UV–visible, PL, and Hall effect measurements. X-ray confirmed the incorporation of aluminum and europium ions into the ZnO structure. All films have polycrystalline nature with hexagonal wurtzite structure at (002) direction. Topological depictions exhibited minimum surface roughness and low film thickness for pristine AZO thin film. EDAX study authorizes the existence of Zn, O, Al, and Eu in Eu: AZO thin films. Raman spectra exhibited the characteristic of ZnO-wurtzite structure (E2-high) mode at 447?cm?1. The deposited film showed high optical transmittance of ~90% in visible region, and the direct energy gap was around 3.30?eV for pristine AZO thin film. The PL spectra emitted a powerful UV emission situated at 388?nm, and it indicates that the film has good optical quality. The obtained large carrier concentration and less resistivity values are 4.42?×?1021?cm?3 and 3.95?×?10?4?Ω?cm, respectively, for 1.5% Eu-doped AZO thin film. The calculated figure of merit value is 17.29?×?10?3 (Ω/sq)?1, which is more suitable for the optoelectronic device.  相似文献   
10.
Journal of Thermal Analysis and Calorimetry - Parked vehicles are vulnerable to cabin overheating, which leads to hyperthermia, accidental death of babies and pets, increased fuel consumption and...  相似文献   
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