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921.
Attainability of the minimum data rate for stabilization of linear systems via logarithmic quantization 总被引:1,自引:0,他引:1
This paper investigates the attainability of the minimum average data rate for stabilization of linear systems via logarithmic quantization. It is shown that a finite-level logarithmic quantizer suffices to approach the well-known minimum average data rate for stabilizing an unstable linear discrete-time system under two basic network configurations. In particular, we derive explicit finite-level logarithmic quantizers and the corresponding controllers to approach the minimum average data rate. 相似文献
922.
In evolutionary multi-objective optimization (EMO), the convergence to the Pareto set of a multi-objective optimization problem (MOP) and the diversity of the final approximation of the Pareto front are two important issues. In the existing definitions and analyses of convergence in multi-objective evolutionary algorithms (MOEAs), convergence with probability is easily obtained because diversity is not considered. However, diversity cannot be guaranteed. By combining the convergence with diversity, this paper presents a new definition for the finite representation of a Pareto set, the B-Pareto set, and a convergence metric for MOEAs. Based on a new archive-updating strategy, the convergence of one such MOEA to the B-Pareto sets of MOPs is proved. Numerical results show that the obtained B-Pareto front is uniformly distributed along the Pareto front when, according to the new definition of convergence, the algorithm is convergent. 相似文献
923.
Carsten Carstensen Xiaoping Xie Guozhu Yu Tianxiao Zhou 《Computer Methods in Applied Mechanics and Engineering》2011,200(9-12):1161-1175
This paper proposes a quadrilateral finite element method of the lowest order for Reissner–Mindlin (R–M) plates on the basis of Hellinger–Reissner variational principle, which includes variables of displacements, shear stresses and bending moments. This method uses continuous piecewise isoparametric bilinear interpolation for the approximation of transverse displacement and rotation. The piecewise-independent shear stress/bending moment approximation is constructed by following a self-equilibrium criterion and a shear-stress-enhanced condition. A priori and reliable a posteriori error estimates are derived and shown to be uniform with respect to the plate thickness t. Numerical experiments confirm the theoretical results. 相似文献
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Guowu YangFei Xie William N.N. Hung Xiaoyu SongMarek A. Perkowski 《Theoretical computer science》2011,412(17):1606-1613
Reversible circuits play an important role in quantum computing. This paper studies the realization problem of reversible circuits. For any n-bit reversible function, we present a constructive synthesis algorithm. Given any n-bit reversible function, there are N distinct input patterns different from their corresponding outputs, where N≤2n, and the other (2n−N) input patterns will be the same as their outputs. We show that this circuit can be synthesized by at most 2n⋅N ‘(n−1)’-CNOT gates and 4n2⋅N NOT gates. The time and space complexities of the algorithm are Ω(n⋅4n) and Ω(n⋅2n), respectively. The computational complexity of our synthesis algorithm is exponentially lower than that of breadth-first search based synthesis algorithms. 相似文献
929.
近几年,各级政府开始要求城市供水企业将高层建筑二次供水纳入日常管理范围,为了达到科学高效的管理目标,提出采用计算机、网络和自控技术对二次供水泵站进行远程监控,并详细介绍了系统的建设目标、建设原则、网络结构、中心端硬软件配置、现场端数据采集和地址分配。该系统实现了不同型号设备跨平台的集成,在实践中具有推广价值。 相似文献
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