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991.
In this paper, notions of fuzzy closure system and fuzzy closure L —system on L —ordered sets are introduced from the fuzzy point of view. We first explore the fundamental properties of fuzzy closure systems. Then the correspondence between fuzzy closure systems (fuzzy closure L —systems) and fuzzy closure operators is established. Finally, we study the connections between fuzzy closure systems and fuzzy Galois connections. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
992.
993.
Hilbert–Huang Transformation and Statistical Theory are used to analyze the impinging flame noise signals of a gasifier. The characteristic of the flame noise energy is studied by standard deviation and probability density, and frequency–time distribution is generated by the empirical mode decomposition (EMD) method and Hilbert spectrum. The results show that, in different conditions, the value of standard deviation of four burners impinging flame noise is greater than that of the two burners, but not for the probability density. The change of the standard deviation and probability density of four burners is smaller than that of two burners. It means that the flame of four burners combusts severely but stably. Under the condition of low feed and oxygen ratio, the two flame burner noise signals frequency and energy distribute mainly in 100 Hz regions; and four burners flame noise distribution is concentrated in the low-frequency bands below 45 Hz and the 45–100 Hz bands. 相似文献
994.
Ronghua Shi Jinjing Shi Ying Guo Xiaoqi Peng Moon Ho Lee 《International Journal of Theoretical Physics》2011,50(8):2334-2346
A novel quantum MIMO communication scheme is proposed by generalizing the wireless communication technique to the quantum
field. The MIMO quantum teleportation can be implemented with triplet states in order to enhance the capacity and fidelity
of the quantum channel, in which an n-qubit sequence of quantum signals can be transmitted through the MIMO quantum channel by applying the diversity technique.
The quantum noise filtering is involved before the quantum signals are outputted. The analysis and discussions demonstrate
that the quantum MIMO teleportation can be performed securely with high capacity and fidelity. 相似文献
995.
Trivalent dysprosium ions (Dy3+) doped strontium molybdate (SrMoO4) phosphors were synthesized by solid-state reaction and their photoluminescence (PL) properties were investigated. X-ray powder diffraction (XRD) analysis confirmed the formation of SrMoO4:Dy3+. PL measurements indicated that the phosphor exhibited intense emission at 482, 490 (4F9/2→6H15/2) and 575 nm (4F9/2→6H13/2) under UV excitation. The effect of the doping concentration of Dy3+in SrMoO4:Dy3+ on the PL was investigated in detail. Na+ ion was a good charge compensator for SrMoO4:Dy3+. 相似文献
996.
Chi-Jen Wang Xiaofang Guo Da-Jiang Liu J. W. Evans 《Journal of statistical physics》2011,144(6):1308-1328
Schloegl’s second model for autocatalysis on a hypercubic lattice of dimension d≥2 involves: (i) spontaneous annihilation of particles at lattice sites with rate p; and (ii) autocatalytic creation of particles at vacant sites at a rate proportional to the number of diagonal pairs of particles
on neighboring sites. Kinetic Monte Carlo simulations for a d=3 cubic lattice reveal a discontinuous transition from a populated state to a vacuum state as p increases above p=p
e
. However, stationary points, p=p
eq (≤p
e
), for planar interfaces separating these states depend on interface orientation. Our focus is on analysis of interface dynamics
via discrete reaction-diffusion equations (dRDE’s) obtained from mean-field type approximations to the exact master equations
for spatially inhomogeneous states. These dRDE can display propagation failure absent due to fluctuations in the stochastic
model. However, accounting for this anomaly, dRDE analysis elucidates exact behavior with quantitative accuracy for higher-level
approximations. 相似文献
997.
By expanding the Debye theory into the tight focusing of partially coherent field, the intensity and spatial correlation properties of partially coherent radially polarized vortex beams are studied. Expressions are derived for the intensity distribution and the spectral degree of coherence in the focal region. It is found that the intensity and the transverse and longitudinal coherence degrees in the focal region change with the variation of the topological charge and coherence length of the vortex beam. In addition, the degree of coherence is shown to exhibit phase singularities. 相似文献
998.
Jiansong Zhang Danping Yang Hongfei Fu Hui Guo 《Numerical Linear Algebra with Applications》2011,18(4):695-705
Based on the overlapping‐domain decomposition and parallel subspace correction method, a new parallel algorithm is established for solving time‐dependent convection–diffusion problem with characteristic finite element scheme. The algorithm is fully parallel. We analyze the convergence of this algorithm, and study the dependence of the convergent rate on the spacial mesh size, time increment, iteration times and sub‐domains overlapping degree. Both theoretical analysis and numerical results suggest that only one or two iterations are needed to reach to optimal accuracy at each time step. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
999.
In this paper, we show the following result: Let K
i
be a knot in a closed orientable 3-manifold M
i
such that (M
i
,K
i
) is not homeomorphic to (S
2 ×S
1, x
0 ×S
1), i = 1, 2. Suppose that the Euler Characteristic of any meridional essential surface in each knot complement E(K
i
) is less than the difference of one and twice of the tunnel number of K
i
. Then the tunnel number of their connected sum will not go down. If in addition that the distance of any minimal Heegaard
splitting of each knot complement is strictly more than 2, then the tunnel number of their connected sum is super additive. 相似文献
1000.
We investigate the Morita context and graded cases for weak group corings and derive some equivalent conditions for μ to be
surjective. Furthermore, we develop Galois theory for weak group corings. As an application, we give Galois theory for comodulelike
algebras over a weak Hopf group coalgebra. 相似文献