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991.
Wen-Jer Chang Liang-Zhi Liu Cheung-Chieh Ku 《International Journal of Control, Automation and Systems》2011,9(3):550-557
This paper investigates the fuzzy control problem of a class of nonlinear continuous-time stochastic systems with achieving
the passivity performance. A model-based observer feedback fuzzy control utilizing the concept of so-called parallel distributed
compensation (PDC) is employed to stabilize the class of nonlinear stochastic systems that are represented by the Takagi-Sugeno
(T-S) fuzzy models. Based on the Lyapunov criteria, the Linear Matrix Inequality (LMI) technique is used to synthesize the
observer feedback fuzzy controller design such that the closed-loop system satisfies stability and passivity constraints,
simultaneously. Finally, a numerical example is given to demonstrate the applicability and effectiveness of the proposed design
method. 相似文献
992.
Electro-osmotically driven displacement between two solutions having a conductivity mismatch is theoretically examined. Internal
pressures induced by the conductivity mismatch can affect the propagation of the solution interface and the behavior of the
transient current. Combining Ohm’s law and fluid mass conservation, we derive a coupled set of length-averaged equations accounting
for how the electric current and the traveling distance of the solution interface vary with time, electric field, and the
solution conductivities. Extension to successive displacements involving multiple solution zones is made to reveal non-monotonic
and stagewise changes in transient currents. For the first time, critical roles of surface conductance on displacements in
highly charged channels are unraveled. We show that if the lower conductivity solution has a greater valence than the higher
one, the effective conductivity of the former can exceed that of the latter when the channel height is below some critical
value. The resulting transient current behavior can turn opposite to that usually observed in the large-channel case, offering
a new paradigm for gauging the importance of surface conductance in submicron charged channels. Possible impacts of diffusion
smearing and hydrodynamic dispersion are also discussed by including the additional mixing zone into the analysis. Having
shown good agreement with the existing experimental data, our analysis not only captures the natures of solution displacement
by electro-osmotic flow (EOF), but also extends the applicability of the current monitoring method for measuring surface zeta
potentials of microchannels. 相似文献
993.
雷达装备测试性验证及应用研究 总被引:2,自引:0,他引:2
针对目前雷达装备测试性论证、设计和验收中缺乏系统、有效的测试性验证方法的问题,提出了适合于雷达装备测试性验证程序和实施方案,重点对测试性定量指标验证样本量的确定方法、故障注入模式的选取原则、故障样本分配以及系统测试性评价进行了研究;该验证方法充分考虑了装备承制方和订购方风险,可用于雷达装备故障检测率、故障隔离率和虚警率的验证与评估;最后进行了实例分析,结果表明该方法能够达到测试性验证的效果,具有一定的实用性和参考价值。 相似文献
994.
计算机数据库的入侵检测技术对计算机的安全运行有着很大的帮助,这是一项积极主动防御外来侵害的高新技术,对计算机数据库可以进行多重保护。检测技术不仅能够对外来的病毒入侵一一攻克,还能对内部的潜在病毒进行查杀,对数据进行保护。 相似文献
995.
996.
基于局域网建立的VLAN技术得到了用户的广泛应用和支持,这也反映了局域网技术必然存在一些特点和优势。本文通过对VLAN技术的特征分析,逐步解译VLAN技术如何在网络安全管理领域发挥各种效用。 相似文献
997.
We present an efficient algorithm for collision detection between static rigid objects using a dual bounding volume hierarchy which consists of an oriented bounding box (OBB) tree enhanced with bounding spheres. This approach combines the compactness of OBBs and the simplicity of spheres. The majority of distant objects are separated using the simpler sphere tests. The remaining objects are in close proximity, where some separation axes are significantly more effective than others. We select 5 from among the 15 potential separating axes for OBBs. Experimental results show that our algorithm achieves considerable speedup in most cases with respect to the existing OBB algorithms. 相似文献
998.
Let S be a set of elements. We say that a collection C of subsets of S has the consecutive ones property if there exist a linear order on S and a 0-1 matrix M, where Mij=1 if and only if the jth element is in the ith set in C, such that all 1's appear consecutively in each row of M. A set X∈C is hit by a subset S′⊆S if X∩S′≠∅. Let Cr (red collection) and Cb (blue collection) be two collections of subsets of S respectively. The red-blue hitting set problem asks for a subset S′⊆S such that all sets in the blue collection are hit by S′, while the number of sets in the red collection hit by S′ has to be minimum. We present a shortest-path based algorithm with time complexity O(|Cb||S|+|Cr||S|+2|S|) for this problem with Cr∪Cb having the consecutive ones property, which improves the previous time bound O(|Cr||Cb|2|S|) by Dom et al. (2008) [8]. 相似文献
999.
An efficient table lookup decoding algorithm (TLDA) is presented to decode up to five possible errors in a binary systematic (47, 24, 11) quadratic residue (QR) code. The main idea of the TLDA is based on the weight of syndrome, the syndrome decoder together with a reduced-size lookup table (RSLT), and the shift-search method given by Reed et al. Thus, the size of the lookup table and computational complexity in a finite field can be significantly reduced. The memory size of the proposed condensed lookup table (CLT) consists of only 36.6 Kbytes and is only about 0.24% of the full lookup table (FLT) and 3.2% of the lookup up table given by Chen et al., respectively. These facts lead to significant reduction of computational time and the decoding complexity. A simulation result shows that the decoding speed of the proposed TLDA is much faster than all existing decoding algorithms. Moreover, it can be extended to decode all QR codes, including the class of the cyclic codes when the code length is moderate. The CLT makes this new decoding algorithm suitable for hardware or firmware implementations. 相似文献
1000.
To provide both a high payload capacity and a good stego-image quality, a high payload frequency-based reversible image hiding (HPFRIH) method was presented in this paper. These performances can be achieved by transforming a cover image from the spatial domain into the frequency domain through Haar digital wavelet transform (HDWT) method followed by an adaptive arithmetic coding method to encode the HDWT coefficients in a high-frequency band. The HPFRIH method was used to conceal both the compressed data and the secret data in the high-frequency band. This simple method can completely reconstruct the cover image only from the stego-image. Moreover, experimental results showed that the HPFRIH method offers both impressive hiding capacity and satisfied stego-image quality. 相似文献