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131.
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133.
研究具有外界持续扰动的时滞非线性大系统的无静差最优跟踪控制问题 .将时滞非线性大系统分解为带有互联项的N个时滞非线性子系统,基于内模原理对子系统构造扰动补偿器,将带有外部持续扰动的子系统化为无扰动的增广系统 .通过灵敏度法求解不含时滞的两点边值问题,得到子系统的最优跟踪控制律,截取最优跟踪控制律的前N项作为次优控制律来近似系统的最优控制律. 仿真实例表明了该设计方法的有效性.
相似文献134.
135.
针对一类带有死区模型并具有未知函数控制增益的不确定MIMO 非线性时滞系统,基于滑模控制原理和Nussbaum函数的性质,提出了一种稳定的自适应神经网络控制方案 .该方案放宽了对函数控制增益上界为未知常数的假设,并通过使用Lyapunov0Krasovski 泛函抵消了因未知时变时滞带来的系统不确定性. 理论分析证明,闭环系统是半全局一致终结有界.仿真结果表明了该方法的有效性.
相似文献136.
Xin-Dong Wu 《计算机科学技术学报》2009,24(6):1018-1027
Due to the increasing availability and sophistication of data recording techniques, multiple information sources and distributed
computing are becoming the important trends of modern information systems. Many applications such as security informatics
and social computing require a ubiquitous data analysis platform so that decisions can be made rapidly under distributed and
dynamic system environments. Although data mining has now been popularly used to achieve such goals, building a data mining
system is, however, a nontrivial task, which may require a complete understanding on numerous data mining techniques as well
as solid programming skills. Employing agent techniques for data analysis thus becomes increasingly important, especially
for users not familiar with engineering and computational sciences, to implement an effective ubiquitous mining platform.
Such data mining agents should, in practice, be intelligent, complete, and compact. In this paper, we present an interactive
data mining agent — OIDM (online interactive data mining), which provides three categories (classification, association analysis,
and clustering) of data mining tools, and interacts with the user to facilitate the mining process. The interactive mining
is accomplished through interviewing the user about the data mining task to gain efficient and intelligent data mining control.
OIDM can help users find appropriate mining algorithms, refine and compare the mining process, and finally achieve the best
mining results. Such interactive data mining agent techniques provide alternative solutions to rapidly deploy data mining
techniques to broader areas of data intelligence and knowledge informatics. 相似文献
137.
Yi-Song Wang 《计算机科学技术学报》2009,24(6):1125-1137
Logic programming under the stable model semantics is proposed as a non-monotonic language for knowledge representation and
reasoning in artificial intelligence. In this paper, we explore and extend the notion of compatibility and the Λ operator, which were first proposed by Zhang to characterize default theories. First, we present a new characterization
of stable models of a logic program and show that an extended notion of compatibility can characterize stable submodels. We further propose the notion of weak auto-compatibility which characterizes the Normal Forward Chaining Construction proposed by Marek, Nerode and Remmel. Previously, this construction was only known to construct the stable models of FC-normal
logic programs, which turn out to be a proper subclass of weakly auto-compatible logic programs. We investigate the properties
and complexity issues for weakly auto-compatible logic programs and compare them with some subclasses of logic programs. 相似文献
138.
Huanyu Zhao 《计算机科学技术学报》2009,24(5):833-843
Peer-to-Peer Desktop Grid (P2PDG) has emerged as a pervasive cyber-infrastructure tackling many large-scale applications with
high impacts. As a burgeoning research area, P2PDG can support numerous applications, including scientific computing, file
sharing, web services, and virtual organization for collaborative activities and projects. To handle trustworthiness issues
of these services, trust and reputation schemes are proposed to establish trust among peers in P2PDG. In this paper, we propose
a robust group trust management system, called H-Trust, inspired by the H-index aggregation technique. Leveraging the robustness
of the H-index algorithm under incomplete and uncertain circumstances, H-Trust offers a robust personalized reputation evaluation
mechanism for both individual and group trusts with minimal communication and computation overheads. We present the H-Trust
scheme in five phases, including trust recording, local trust evaluation, trust query phase, spatial-temporal update phase,
and group reputation evaluation phases. The rationale for its design, the analysis of the algorithm are further investigated.
To validate the performance of H-Trust scheme, we designed the H-Trust simulator HTrust-Sim to conduct multi-agent-based simulations.
Simulation results demonstrate that H-Trust is robust and can identify and isolate malicious peers in large scale systems
even when a large portion of peers are malicious. 相似文献
139.
基于证据理论研究直觉模糊集隶属度和非隶属度函数的确定问题是一种新的思路.首先分析信任函数,似然函数与隶属度函数,非隶属度函数的互通性;然后给出广义基本概率分配(BPA)函数,广义信任函数和广义似然函数的定义;最后在这3个改进定义的基础上建立直觉模糊集隶属度函数,非隶属度函数模型,通过证明和实例验证了模型的正确性和有效性.
相似文献140.