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排序方式: 共有624条查询结果,搜索用时 31 毫秒
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Nonlinear Dynamics - In this paper, a class of switched fractional-order continuous-time systems with order $$0<\alpha <1$$ is investigated. First, an interesting property of... 相似文献
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Cobalt-free perovskite oxide La0.5Sr0.5Fe0.8Cu0.2O3 − δ (LSFC) was applied as both anode and cathode for symmetrical solid oxide fuel cells (SSOFCs). The LSFC shows a reversible transition between a cubic perovskite phase in air and a mixture of SrFeLaO4, a K2NiF4-type layered perovskite oxide, metallic Cu and LaFeO3 in reducing atmosphere at elevated temperature. The average thermal expansion coefficient of LSFC in air is 17.7 × 10− 6 K− 1 at 25 °C to 900 °C. By adopting LSFC as initial electrodes to fabricate electrolyte supported SSOFCs, the cells generate maximum power output of 1054, 795 and 577 mW cm− 2 with humidified H2 fuel (~ 3% H2O) and 895, 721 and 482 mW cm− 2 with humidified syngas fuel (H2:CO = 1:1) at 900, 850 and 800 °C, respectively. Moreover, the cell with humidified H2 fuel demonstrates a reasonable stability at 800 °C under 0.7 V for 100 h. 相似文献
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Images captured by image acquisition systems using photon-counting devices such as astronomical imaging, positron emission tomography and confocal microscopy imaging, are often contaminated by Poisson noise. Total variation (TV) regularization, which is a classic regularization technique in image restoration, is well-known for recovering sharp edges of an image. Since the regularization parameter is important for a good recovery, Chen and Cheng (2012) proposed an effective TV-based Poissonian image deblurring model with a spatially adapted regularization parameter. However, it has drawbacks since the TV regularization produces staircase artifacts. In this paper, in order to remedy the shortcoming of TV of their model, we introduce an extra high-order total variation (HTV) regularization term. Furthermore, to balance the trade-off between edges and the smooth regions in the images, we also incorporate a weighting parameter to discriminate the TV and the HTV penalty. The proposed model is solved by an iterative algorithm under the framework of the well-known alternating direction method of multipliers. Our numerical results demonstrate the effectiveness and efficiency of the proposed method, in terms of signal-to-noise ratio (SNR) and relative error (RelRrr). 相似文献
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We prepose a 5-bit lattice Boltzmann model for KdV equation. Using Chapman-Enskog expansion and multiscale technique, we obtained
high order moments of equilibrium distribution function, and the 3rd dispersion coefficient and 4th order viscosity. The parameters
of this scheme can be determined by analysing the energy dissipation.
The project supported by the Foundation of the Laboratory for Nonlinear Mechanics of Continuous Media, Institute of Mechanics,
Chinese Academy of Sciences 相似文献
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In this paper, the proposed is a quasi-flow constitutive model with strain-rate sensitivity for elastic plastic large deformation.
The model is based on the Quasi-flow Corner theory, and is suitable for the sheet metal forming process simulation with a
variable punch machine velocity. Uniaxial tensile tests and deep-drawing tests of a circular blank with square punch are carried
out and numerically simulated. The consistency between the experimental and the numerically simulated results shows the validity
of the present new constitutive model.
The project supported by the Scientific Foundation of National Outstanding Youth of China (10125208), the National Natural
Science Foundation of China (19832020), and the National Education Committee of China 相似文献
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In this paper, a shape optimization problem, modelling a welding process, governed by a second order non coercive PDE is considered. The well posedness of the shape optimal design problem is showed using the degree of Leray–Schauder. Then the existence of an optimal solution is proved. 相似文献