A novel image deblurring method based on high-order non-local range Markov Random Field (NLR-MRF) prior is proposed in the paper. NLR-MRF provides an effective framework to model the statistical prior of natural image...
详细信息
A novel image deblurring method based on high-order non-local range Markov Random Field (NLR-MRF) prior is proposed in the paper. NLR-MRF provides an effective framework to model the statistical prior of natural images and leads to excellent performance in the application of image denoising and inpainting. Moreover, the framework will be extended to image deblurring in our work. Instead of commonly used maximum a-posteriori (MAP) estimation, which has several shortcomings, the high-order NLR-MRF prior is integrated into Bayesian minimum mean squared error (MMSE) estimation framework. Then, an efficient Gibbs sampling algorithm is adopted to compute MMSE estimation. The proposed method frees the user from determining regularization parameter beforehand, which relies on unknown noise level. We perform experiments on synthetic and real-world data to demonstrate the effectiveness of our method. Both quantitatively and qualitatively evaluations show superior or comparable results to the state-of-art deblurring methods.
Turbulent fluidized bed reactors are widely used in industry. However, CFD simulations of the hydrody- namic characteristics of these reactors are relatively sparse, despite the urgent demand from industry. To address...
详细信息
Turbulent fluidized bed reactors are widely used in industry. However, CFD simulations of the hydrody- namic characteristics of these reactors are relatively sparse, despite the urgent demand from industry. To address this problem, Eulerian simulations with an EMMS-based sub-grid scale model, accounting for the effect of sub-grid scale structures on the inter-phase friction, are performed to study the hydrodynamics inside a large-scale turbulent fluidized bed of FCC particles. It is shown that the simulated axial and radial solid concentration profiles, entrained solid fluxes and standard deviation of the solid concentration fluc- tuation agreed well with experimental data available in the literature. In-depth analysis of time-averaged particle velocity and solid concentration shows that a dense-suspension upflow regime coexists with fast fluidization regime in this bed, which is reminiscent of the hydrodynamic characteristics in high-density circulating fluidized bed （CFB） risers, even though they are operated in different fluidization regimes. The Reynolds stresses in turbulent fluidized beds are anisotropic, but the degree of anisotropy is far less pro- nounced than the reported values in CFB risers. It was also found that the solid concentration fluctuation and axial particle velocity fluctuation are strongly correlated. 2009 Chinese Society of Particuology and institute of processengineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.
The far-field intensity is detected from far-field image to estimate the piston distance between two gratings. The image processing algorithm includes projections along the horizontal and vertical directions, sear...
详细信息
The far-field intensity is detected from far-field image to estimate the piston distance between two gratings. The image processing algorithm includes projections along the horizontal and vertical directions, search for each focal spot's centre, feature extraction and intensity computation. Each focal spot's centre can be found with the projections. A self-growing method is used for feature extraction, where the threshold value depends on the gray value of each focal spot's centre. For each focal spot, the sum of gray values within the relevant domain is taken to be its energy intensity. Furthermore, the energy ratio of left and main focal spots (or main and right focal spots) is computed. A formula that expresses the piston distance between two gratings as the function of the energy ratio is fitted with several measured points. Based on this formula, the piston distance is obtained for a new energy-ratio. Finally, the proposed method is verified with a series of experiments.
Intensity inhomogeneous images, especially medical images, widely exist in real world. Considering that the existing methods can not solve intensity inhomogeneous images segmentation properly, this paper proposes a re...
详细信息
Intensity inhomogeneous images, especially medical images, widely exist in real world. Considering that the existing methods can not solve intensity inhomogeneous images segmentation properly, this paper proposes a region-based active contour model with neighborhood information. Different from existing models using global region information, the new model incorporates local information of an image into a level set formulation. By defining a new energy functional for every pixel in the image domain and utilizing the information of neighborhoods, the proposed model has the ability to extract local details, thus can segment images with intensity inhomogeneity. We also present a new approximation of the Heaviside function and Dirac function. Experimental results demonstrate that the new model has desirable performance, which is more precise than the Chan-Vese model and much faster than the Piecewise Smooth model.
Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and...
详细信息
Thermodynamic models of calculating mass action concentrations for structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions were developed based on the ion and molecule coexistence theory at 298.15 K.A transformation coefficient is needed to compare the calculated mass action concentration and the reported activity because they are obtained at different standard states and concentration *** results show that the transformation coefficients between the calculated mass action concentrations and the reported activities of the same structural units or ion couples in RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions change in a very narrow *** transformed mass action concentrations of structural units or ion couples in RbCl-H2O binary system are in good agreement with the reported activities. The transformed mass action concentrations of RbCl and RbNO3 in RbCl-RbNO3-H2O ternary solution are also in good agreement with the reported activities,aRbCl and 3RbNOa,with different total ionic strengths as 0.01,0.05,0.1,0.5,1.0,1.5,2.0,3.0 and 3.5 mol/kg,*** those results mean the developed thermodynamic model of strong electrolyte aqueous solutions can reflect structural characteristics of RbCl-H2O binary and RbCl-RbNO3-H2O ternary strong electrolyte aqueous solutions and the mass action concentration also strictly follows the mass action law.
作者：
Lin YeYouhong TangDonghai ZhangCentre for Advanced Materials Technology
School of Aerospace Mechanical and Mechatronic Engineering The University of Sydney NSW 2006 Australia State Key Laboratory of Multi-phase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China
A coupled numerical method for the direct numerical simulation of particle-fluid systems is formulated and implemented, resolving an order of magnitude smaller than particle size. The particle motion is described by t...
详细信息
A coupled numerical method for the direct numerical simulation of particle-fluid systems is formulated and implemented, resolving an order of magnitude smaller than particle size. The particle motion is described by the time-driven hard-sphere model, while the hydrodynamic equations governing fluid flow are solved by the lattice Boltzmann method （LBM）, Particle-fluid coupling is realized by an immersed boundary method （IBM）, which considers the effect of boundary on surrounding fluid as a restoring force added to the governing equations of the fluid. The proposed scheme is validated in the classical flow-around-cylinder simulations, and preliminary application of this scheme to fluidization is reported, demonstrating it to be a promising computational strategy for better understanding complex behavior in particle-fluid systems.
暂无评论