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991.
In this paper, we introduce two novel split least-squares mixed element procedures for pseudo-parabolic equations. By selecting the least-squares functional properly, each procedure can be split into two independent symmetric positive definite sub-procedures. One of sub-procedures is for the primitive unknown variable u, which is the same as the standard Galerkin finite element procedure and the other is for the introduced flux variable σ. Optimal order error estimates are developed. A numerical example is given to show the efficiency of the introduced schemes.  相似文献   
992.
A GI/G/1 queue with vacations is considered in this paper.We develop an approximating technique on max function of independent and identically distributed(i.i.d.) random variables,that is max{ηi,1 ≤ i ≤ n}.The approximating technique is used to obtain the fluid approximation for the queue length,workload and busy time processes.Furthermore,under uniform topology,if the scaled arrival process and the scaled service process converge to the corresponding fluid processes with an exponential rate,we prove by the...  相似文献   
993.
In this paper,the existence of global attractor for 3-D complex Ginzburg Landau equation is considered.By a decomposition of solution operator,it is shown that the global attractor A_i in H~i(Ω) is actually equal to a global attractor Aj in H~j(Ω)(i≠j,i,j = 1,2,…m).  相似文献   
994.
Let K be a knot in a sphere S3. We denote by t(K) the tunnel number of K. For two knots K1 and K2, we denote by K1?K2 the connected sum of K1 and K2. In this paper, we will prove that if one of K1 and K2 has high distance while the other has distance at least 3 then t(K1?K2)=t(K1)+t(K2)+1.  相似文献   
995.
This paper deals with the stochastic 2D Boussinesq equations with partial viscosity. This is a coupled system of Navier-Stokes/Euler equations and the transport equation for temperature under additive noise. Global well-posedness result of this system under partial viscosity is proved by using classical energy estimates method.  相似文献   
996.
In this paper, a powerfully analytical technique is proposed for predicting and generating the steady state solution of the fractional differential system based on the method of harmonic balance. The zeroth-order approximation using just one Fourier term is applied to predict the parametric function for the boundary between oscillatory and non-oscillatory regions of the fractional van der Pol oscillator. The unbalanced residues due to Fourier truncation are considered iteratively by solving linear algebraic equations to improve the accuracy of the solutions successively. The highly accurate solutions to the angular frequency and limit cycle of fractional van der Pol oscillator are obtained and compared. The results reveal that the technique described in this paper is very effective and simple for obtaining asymptotic solution of nonlinear system having fractional order derivative.  相似文献   
997.
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   
998.
基于灰色聚类分析的企业应急管理能力评价   总被引:2,自引:0,他引:2  
张国辉  吴艳  张蜜 《经济数学》2011,28(1):94-99
在对企业应急管理能力概念初步界定的基础上,建立企业应急管理能力评价指标体系,针对企业应急管理能力多指标综合评价中存在的主观性问题,依据灰色聚类原理,提供了一种计算各指标权重的方法,使得指标之间的权重在评价过程中自动产生,不需要经过人为判断,减少了评价过程中的主观因素.结合实例企业,通过专家对各指标进行评估打分,根据评价...  相似文献   
999.
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   
1000.
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   
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