Hardware accelerator for anti-aliasing Wu's line algorithm using FPGA

Digital images are suffering from the stair-step effect because they are built from small pixels. This effect termes aliasing and the method uses to decrease so-called anti-aliasing. This paper offers a hardware accelerator of an anti-aliasing algorithm using HLS (high level synthesis) along straight-line segments or edges. These straight-line segments are smoothed by modifying the intensity of the pixel. The hardware implementation of two different architectures which is based on Zynq FPGA are presented in this work. The first architecture is built from one core while the second architecture is built from multi-core and uses a parallel technique to speed up the algorithm by dividing line segments into sub-segments and drawing them after smoothing instantaneously to formulate the main line. This parallel usage leads to a very fast execution of Wu's algorithm which is represented one-tenth hardware runtime for one core only. Also, the optimized resource utilization and power consumption for different cores have been compared, through single-core design which utilizes 8% and consumes 1.6 W, while utilized resources using 10 cores are 77% with a power consumption of 2 W

Fourier transforms of Lipschitz functions on certain Lie groups

We study the order of magnitude of the Fourier transforms of certain Lipschitz functions on the special linear group of real matrices of order two

Strangeness production at finite temperature and baryon density in an effective relativistic mean field model

We study the strangeness production in hot and dense nuclear medium, by requiring the conservation of the baryon density, electric charge fraction and zero net strangeness. The hadronic equation of state is investigated by means of an effective relativistic mean field model, with the inclusion of the full octet of baryons and kaon mesons. Kaons are considered taking into account of an effective chemical potential depending on the self-consistent interaction between baryons. The obtained results are compared with a minimal coupling scheme, calculated for different values of the anti-kaon optical potential and with non-interacting kaon particles. In this context, we also consider the possible onset of the kaon condensation for a wide range of temperatures and baryon densities.Comment: 13 pages, 6 figure

A piecewise-linear reduced-order model of squeeze-film damping for deformable structures including large displacement effects

This paper presents a reduced-order model for the Reynolds equation for deformable structure and large displacements. It is based on the model established in [11] which is piece-wise linearized using two different methods. The advantages and drawbacks of each method are pointed out. The pull-in time of a microswitch is determined and compared to experimental and other simulation data.Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/handle/2042/16838

Statistical Inference of Weibull Extension Distribution under Imprecise Data

In this paper, we present the maximum likelihood (ML) and Bayes estimation of the unknown parameters, the reliability and hazard functions of the Weibull extension distribution based on progressively Type-II censoring scheme from fuzzy lifetime data. For the computation of Bayes estimates, we proposed using Tierney-Kadane’s approximation under square error and LINEX loss functions. The performance of the maximum likelihood and Bayes estimators compared in terms of their mean squared errors (MSEs) through the simulation study. The results indicated that MSEs based on Tierney-Kadane’s approximation are less than based on the ML method. Finally, to demonstrate the efficiency of the proposed methods, two real data sets are analyzed

Chemical reactivity and structural determination of metal and gaseous adsorbates on Cu{100} using TPD and LEED

The structures formed by adsorbing thin-film platinum, formic acid and oxygen on Cu{ 100} single crystal are investigated by quantitative low-energy electrondiffraction (LEED) and Temperature Programmed Reaction Spectroscopy (TPRS) Symmetrized Automated Tensor LEED (SATLEED) calculations are used to determine the structure of the formed surface alloys and overlayers. TPRS was used to probe the surface reactivity of the systems studied while surface composition was obtained using Auger Electron spectroscopy (AES). The decomposition of a formate intermediate from a clean Cu(100) surface has been monitored through the use of TPD Spectroscopy CO2 evolution was observed at -440K. The presence of repulsive lateral interactions between the adsorbates on the surface has been identified, through the shift of the peak temperature Tp to lower values, as the surface was exposed to increasing amounts of formic acid. The Tp for 0 5L was observed at 458K,while that for SOL appears at 443K This shift means that the decomposition energy is reduced by 6%. It has also been evidenced that platinum has a destabilising effect on the formate intermediate. The peak temperature (Tp) for the CO2 desorption spectra from copperplatinum model surfaces, appear around 40K lower than those from clean copper. This suggests a much less stable surface alloy compared to the clean surface. In activation energy terms, this destabilisation can be expressed as a 13% decrease in the energy required for the formate to decompose. It was also observed that desorption is much more rapid from the copper-platinum than from clean copper surfaces. More study is needed to fully understand these results. A Cu{100}-c(2x2)-Pt surface alloy structure formed by deposition of 1ML mono layer of Pt and thermal processing to 550K is shown to correspond to a coppercapped bimetallic surface localised alloy with a sub-surface ordered c(2x2) CuPt layer. The layerwise compositional profile has been extracted via ATA modelling resulting in an almost pure outermost copper monolayer with only a small Pt impurity concentration (10± 10 at%) Layers 3 and 4 contained higher Pt concentrations of 20+20 and 30±30 at% respectively. Substitution of platinum into the selvedge results in a significant expansion in the surface mterlayer spacmgs relative to clean Cu{100} and switches the weak oscillatory relaxation of clean Cu{100} to a strongly and non-uniformly expanded interlayer separation. The outermost three mterlayer spacings are strongly expanded to 1 84+0 02A (+1 9±1 1%), 1 91+0 03A (+5 8±1 7%) and 1 89±0 03A (+4 7±1 7%) respectively. A slight rippling in the c(2x2) CuPt underlayer of amplitude 0 03±0 04A, with Pt atoms rippled outwards towards the vacuum interface within the composite layer occurs. A Pt/Cu{100}-(2x2)-0 surface alloy structure, formed by deposition of a high Pt loading and thermal processing in an oxygen atmosphere, is shown to correspond to an oxygen overlayer on a copper-capped bimetallic surface localised alloy with an ordered c(2x2) CuPt monolayer in layers 2 and 4. The selvedge structure within the LEED probing depth strongly resembles the {100} surface of the LI2 phase of the bulk Cu3Pt alloy. Substitution of platinum into the selvedge results in a significant expansion in the surface mterlayer spacmgs relative to Cu{100}-(2V2xV2)R45°-0 due to the larger metallic radius of Pt and switches the weak oscillatory relaxation of Cu{100}-(2>/2xV2)R450-0 to a strongly and non-umformly expanded mterlayer separation. The outermost three interlayer spacmgs are expanded with a slight rippling in the first CuPt underlayer with Pt atoms rippled outwards towards the vacuum interface within the composite layer

On the prediction of turbulent secondary flows

The prediction of turbulent secondary flows, with Reynolds stress models, in circular pipes and non-circular ducts is reviewed. Turbulence-driven secondary flows in straight non-circular ducts are considered along with turbulent secondary flows in pipes and ducts that arise from curvature or a system rotation. The physical mechanisms that generate these different kinds of secondary flows are outlined and the level of turbulence closure required to properly compute each type is discussed in detail. Illustrative computations of a variety of different secondary flows obtained from two-equation turbulence models and second-order closures are provided to amplify these points

Localized Computation of Newton Updates in Fully-implicit Two-phase Flow Simulation

AbstractFully-Implicit (FI) Methods are often employed in the numerical simulation of large-scale subsurface flows in porous media. At each implicit time step, a Newton-like method is used to solve the FI discrete nonlinear algebraic system. The linear solution process for the Newton updates is the computational workhorse of FI simulations. Empirical observations suggest that the computed Newton updates during FI simulations of multiphase flow are often sparse. Moreover, the level of sparsity observed can vary dramatically from iteration to the next, and across time steps. In several large scale applications, it was reported that the level of sparsity in the Newton update can be as large as 99%. This work develops a localization algorithm that conservatively predetermines the sparsity pattern of the Newton update. Subsequently, only the flagged nonzero components of the system need be solved. The localization algorithm is developed for general FI models of two phase flow. Large scale simulation results of benchmark reservoir models show a 10 to 100 fold reduction in computational cost for homogeneous problems, and a 4 to 10 fold reduction for strongly heterogeneous problems