2,946 research outputs found

    Non-minimal Derivative Coupling Scalar Field and Bulk Viscous Dark Energy

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    Inspired by thermodynamical dissipative phenomena, we consider bulk viscosity for dark fluid in a spatially flat two-component Universe. Our viscous dark energy model represents Phantom crossing avoiding Big-Rip singularity. We propose a non-minimal derivative coupling scalar field with zero potential leading to accelerated expansion of Universe in the framework of bulk viscous dark energy model. In this approach, coupling constant (κ\kappa) is related to viscosity coefficient (γ\gamma) and energy density of dark energy at the present time (ΩDE0\Omega_{\rm DE}^0). This coupling is bounded as κ[1/9H02(1ΩDE0),0]\kappa\in [-1/9H_0^2(1-\Omega_{\rm DE}^0), 0] and for γ=0\gamma=0 leads to κ=0\kappa=0. To perform robust analysis, we implement recent observational data sets including Joint Light-curve Analysis (JLA) for SNIa, Gamma Ray Bursts (GRBs) for most luminous astrophysical objects at high redshifts, Baryon Acoustic Oscillations (BAO) from different surveys, Hubble parameter from HST project, {\it Planck} data for CMB power spectrum and CMB Lensing. Joint analysis of JLA++GRBs++BAO++HST shows that ΩDE0=0.696±0.010\Omega_{\rm DE}^0=0.696\pm 0.010, γ=0.1404±0.0014\gamma=0.1404\pm0.0014 and H0=68.1±1.3H_0=68.1\pm1.3 at 1σ1\sigma confidence interval. {\it Planck} TT observation provides γ=0.320.26+0.31\gamma=0.32^{+0.31}_{-0.26} at 68%68\% confidence limit for viscosity coefficient. Tension in Hubble parameter is alleviated in this model. Cosmographic distance ratio indicates that current observed data prefer to increase bulk viscosity. Finally, the competition between Phantom and Quintessence behavior of viscous dark energy model can accommodate cosmological old objects reported as a sign of age crisis in Λ\LambdaCDM model.Comment: 21 pages and 18 figures, some typos in equations fixe

    Design and analysis of a novel low PDP full adder cell

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    This paper, presents a new full-swing low power high performance full adder circuit in CMOS technology. It benefits from a full swing XOR-XNOR module with no feedback transistors, which decreases delay and power consumption. In addition, high driving capability of COUT module and low PDP design of SUM module contribute to more PDP reduction in cascaded mode. In order to have accurate analysis, the new circuit along with several well-known full adders from literature have been modeled and compared with CADENCE. Comparison consists of power consumption, performance, PDP, and area. Results show that there are improvements in both power consumption and performance. This design trades area with low PDP

    Mutually Uncorrelated Primers for DNA-Based Data Storage

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    We introduce the notion of weakly mutually uncorrelated (WMU) sequences, motivated by applications in DNA-based data storage systems and for synchronization of communication devices. WMU sequences are characterized by the property that no sufficiently long suffix of one sequence is the prefix of the same or another sequence. WMU sequences used for primer design in DNA-based data storage systems are also required to be at large mutual Hamming distance from each other, have balanced compositions of symbols, and avoid primer-dimer byproducts. We derive bounds on the size of WMU and various constrained WMU codes and present a number of constructions for balanced, error-correcting, primer-dimer free WMU codes using Dyck paths, prefix-synchronized and cyclic codes.Comment: 14 pages, 3 figures, 1 Table. arXiv admin note: text overlap with arXiv:1601.0817
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