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991.
Let F be a set of f?2n-5 faulty nodes in an n-cube Qn such that every node of Qn still has at least two fault-free neighbors. Then we show that Qn-F contains a path of length at least 2n-2f-1 (respectively, 2n-2f-2) between any two nodes of odd (respectively, even) distance. Since the n-cube is bipartite, the path of length 2n-2f-1 (or 2n-2f-2) turns out to be the longest if all faulty nodes belong to the same partite set. As a contribution, our study improves upon the previous result presented by [J.-S. Fu, Longest fault-free paths in hypercubes with vertex faults, Information Sciences 176 (2006) 759-771] where only n-2 faulty nodes are considered. 相似文献
992.
Genetic programming-based attenuation relationship: An application of recent earthquakes in turkey 总被引:2,自引:0,他引:2
This study investigates an application of genetic programming (GP) for the prediction of peak ground acceleration (PGA) using strong-ground-motion data from Turkey. The input variables in the developed GP model are the average shear-wave velocity, earthquake source to site distance and earthquake magnitude, and the output is the PGA values. The proposed GP model is based on the most reliable database compiled for earthquakes in Turkey. The results show that the consistency between the observed PGA values and the predicted ones by the GP model yields relatively high correlation coefficients (R2=0.75). The proposed model is also compared with an existing attenuation relationship and found to be more accurate. 相似文献
993.
Block preconditioner with circulant blocks (BPCB) has been used for solving linear systems with block Toeplitz structure since 1992 [R. Chan, X. Jin, A family of block preconditioners for block systems, SIAM J. Sci. Statist. Comput. (13) (1992) 1218–1235]. In this new paper, we use BPCBs to general linear systems (with no block structure usually). The BPCBs are constructed by partitioning a general matrix into a block matrix with blocks of the same size and then applying T. Chan’s optimal circulant preconditioner [T. Chan, An optimal circulant preconditioner for Toeplitz systems, SIAM J. Sci. Statist. Comput. (9) (1988) 766–771] to each block. These BPCBs can be viewed as a generalization of T. Chan’s preconditioner. It is well-known that the optimal circulant preconditioner works well for solving some structured systems such as Toeplitz systems by using the preconditioned conjugate gradient (PCG) method, but it is usually not efficient for solving general linear systems. Unlike T. Chan’s preconditioner, BPCBs used here are efficient for solving some general linear systems by the PCG method. Several basic properties of BPCBs are studied. The relations of the block partition with the cost per iteration and the convergence rate of the PCG method are discussed. Numerical tests are given to compare the cost of the PCG method with different BPCBs. 相似文献
994.
In this paper, the robust fault detection filter design problem for linear time invariant (LTI) systems with unknown inputs and modeling uncertainties is studied. The basic idea of our study is to formulate the robust fault detection filter design as a H∞ model-matching problem. A solution of the optimal problem is then presented via a linear matrix inequality (LMI) formulation. The main results include the formulation of robust fault detection filter design problems, the derivation of a sufficient condition for the existence of a robust fault detection filter and construction of a robust fault detection filter based on the iterative of LMI algorithm. 相似文献
995.
Modular redundancy and temporal redundancy are traditional techniques to increase system reliability. In addition to being used as temporal redundancy, with
technology advancements, slack time in a system can also be used by energy management schemes to save energy. In this paper,
we consider the combination of modular and temporal redundancy to achieve energy efficient reliable real-time service provided
by multiple servers. We first propose an efficient adaptive parallel recovery scheme that appropriately processes service requests in parallel to increase the number of faults that can be tolerated and
thus system reliability. Then we explore schemes to determine the optimal redundant configurations of the parallel servers to minimize system energy consumption for a given reliability goal or to maximize system reliability
for a given energy budget. Our analysis results show that small requests, optimistic approaches, and parallel recovery favor
lower levels of modular redundancy, while large requests, pessimistic approaches and restricted serial recovery favor higher
levels of modular redundancy.
相似文献
Daniel MosséEmail: |
996.
The problem of global asymptotic stability analysis is studied for a class of cellular neural networks with time-varying delay. By defining a Lyapunov–Krasovskii functional, a new delay-dependent stability condition is derived in terms of linear matrix inequalities. The obtained criterion is less conservative than some previous literature because free-weighting matrix method and the Jensen integral inequality are considered. Three illustrative examples are given to demonstrate the effectiveness of the proposed results. 相似文献
997.
Synchronization analysis of coupled connected neural networks with mixed time delays 总被引:2,自引:0,他引:2
In this paper, the global exponential synchronization of coupled connected neural networks with both discrete and distributed delays is investigated under mild condition, assuming neither the differentiability and strict monotonicity for the activation functions nor the diagonal for the inner coupling matrices. By employing a new Lyapunov–Krasovskii functional, applying the theory of Kronecker product of matrices and the linear matrix inequality (LMI) technique, several delay-dependent sufficient conditions in LMI form are obtained for global exponential synchronization of such systems. Moreover, the decay rate is estimated. The proposed LMI approach has the advantage of considering the difference of neuronal excitatory and inhibitory efforts, which is also computationally efficient as it can be solved numerically using efficient Matlab LMI toolbox, and no tuning of parameters is required. In addition, the proposed results generalize and improve the earlier publications. An example with simulation is given to show the effectiveness of the obtained results. 相似文献
998.
回归关系推断是统计分析领域中的重要基础内容,其运算形式较为复杂,导致了安全解决方案的效率低下.为了解决安全双方模型下多元回归的统计推断问题,提出极大似然估计、残差平方和与总平方和的安全协议.并依据运算本身的特点,经过对共享矩阵连乘操作规律的数学分析,提出简化运算的方法,使得交互次数大幅减少.同时对其可应用领域进行了展望. 相似文献
999.
一类Lyapunov型矩阵方程组的中心对称解及其最佳逼近 总被引:1,自引:1,他引:0
建立了求矩阵方程组AiXBi+GiXDi=Fi(i=1,2)的中心对称解的迭代算法.使用该方法不仅可以判断矩阵方程组是否有中心对称解,而且在有中心对称解时,还能够在有限步迭代计算之后得到矩阵方程组的极小范数中心对称解.同时,也能够在矩阵方程组的中心对称解集合中求得给定矩阵的最佳逼近. 相似文献
1000.