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991.
An ideal way of obtaining an optimal inspection permutation for a system with components connected in series
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Honest Walter Chipoyera 《商业与工业应用随机模型》2016,32(6):825-835
The problem of an inspection permutation or inspection strategy (first discussed in a research paper in 1989 and reviewed in another research paper in 1991) is revisited. The problem deals with an N‐component system whose times to failure are independent but not identically distributed random variables. Each of the failure times follows an exponential distribution. The components in the system are connected in series such that the failure of at least one component entails the failure of the system. Upon system failure, the components are inspected one after another in a hierarchical way (called an inspection permutation) until the component causing the system to fail is identified. The inspection of each component is a process that takes a non‐negligible amount of time and is performed at a cost. Once the faulty component is identified, it is repaired at a cost, and the repair process takes some time. After the repair, the system is good as new and is put back in operation. The inspection permutation that results in the maximum long run average net income per unit of time (for the undiscounted case) or maximum total discounted net income per unit of time (for the discounted case) is called the optimal inspection permutation/strategy. A way of determining an optimal inspection permutation in an easier fashion, taking advantage of the improvements in computer software, is proffered. Mathematica is used to showcase how the method works with the aid of a numerical example. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
992.
EVANS FUNCTIONS AND INSTABILITY OF A STANDING PULSE SOLUTION OF A NONLINEAR SYSTEM OF REACTION DIFFUSION EQUATIONS
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Linghai Zhang 《应用数学年刊》2016,32(1):79-101
In this paper, we consider a nonlinear system of reaction diffusion equations arising from mathematical neuroscience and two nonlinear scalar reaction diffusion equations under some assumptions on their coefficients. The main purpose is to couple together linearized stability criterion (the equivalence of the nonlinear stability, the linear stability and the spectral stability of the standing pulse solutions) and Evans functions to accomplish the existence and instability of standing pulse solutions
of the nonlinear system of reaction diffusion equations and the nonlinear scalar reaction diffusion equations. The Evans functions for the standing pulse solutions are constructed explicitly. 相似文献
993.
The global well-posedness for the 2D Leray-<Emphasis Type="Italic">α</Emphasis> MHD equations with zero magnetic diffusivity
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Qiong Lei Chen 《数学学报(英文版)》2016,32(10):1145-1158
By means of Fourier frequency localization and Bony’s paraproduct decomposition, we study the global existence and the uniqueness of the 2D Leray-α Magneta-hydrodynamics model with zero magnetic diffusivity for the general initial data. In view of the profits bring by the α model, then using the energy estimate in the frequency space and the Logarithmic Sobolev inequality, we obtain the estimate \(\int_0^t {{{\left\| {{\nabla _u}} \right\|}_L}\infty ds} \)which is crucial to get the global existence for the general initial data. 相似文献
994.
Regularity criterion of weak solutions to the 3D Navier-Stokes equations via two velocity components 总被引:1,自引:0,他引:1
This paper is concerned with the regularity criterion of Leray-Hopf weak solutions to the 3D Navier-Stokes equations with respect to Serrin type condition on two velocity filed components. It is shown that the weak solution u=(u1,u2,u3) is regular on (0,T] if there exist two solution components, for example, u2 and u3, satisfying the condition
995.
Alexander V. Kolesnikov 《Probability Theory and Related Fields》2008,140(1-2):1-17
Let γ be a Gaussian measure on a Suslin space X, H be the corresponding Cameron–Martin space and {e
i
} ⊂ H be an orthonormal basis of H. Suppose that μ
n
= ρ
n
· γ is a sequence of probability measures which converges weakly to a probability measure μ = ρ · γ Consider a sequence of Dirichlet forms , where and . We prove some sufficient conditions for Mosco convergence where . In particular, if X is a Hilbert space, and can be uniformly approximated by finite dimensional conditional expectations for every fixed e
i
, then under broad assumptions Mosco and the distributions of the associated stochastic processes converge weakly. 相似文献
996.
997.
Stanislav Shkarin 《Proceedings of the American Mathematical Society》2008,136(5):1659-1670
It is proved that for any separable infinite dimensional Banach space , there is a bounded linear operator on such that satisfies the Kitai criterion. The proof is based on a quasisimilarity argument and on showing that satisfies the Kitai criterion for certain backward weighted shifts .
998.
耿贵珍 《数学的实践与认识》2016,(10):169-173
根据线性回归模型Y=Xβ+ε,E(ε)=0,COV(ε)=σ~2I,对回归系数的有偏估计c-(K,S)型估计进一步研究;讨论了c-(K,S)型估计的优良性,在一定的条件下获得β_c(K,S)估计与LS估计的相对效率的界,并由此得出在设计阵病态时,β_c(K,S)型估计的精度明显高于LS估计;最后,证明了c-(K,S)型估计的可容许性,从而有助于病态线性回归系数有偏估计的进一步改进. 相似文献
999.
Jitao Liu 《Mathematical Methods in the Applied Sciences》2016,39(15):4535-4544
This paper is concerned with the regularity criterion for a class of axisymmetric solutions to 3D incompressible magnetohydrodynamic equations. More precisely, for the solutions that have the form of u = urer+uθeθ+uzez and b = bθeθ, we prove that if |ru(x,t)|≤C holds for ?1≤t < 0, then (u,b) is regular at time zero. This result can be thought as a generalization of recent results in for the 3D incompressible Navier‐Stokes equations. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
1000.
本文研究了三维空间中磁场微极流方程组弱解的正则性准则问题.利用能量估计的方法证明了如果速度场以及磁场满足一定的条件,则弱解在(0,T]是唯一的强解. 相似文献