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This paper is concerned with asynchronous stabilization for a class of discrete-time Markovian jump systems. The mode of designed controller is considered to be not perfectly synchronous with the activated mode of the Markovian jump system. In order to achieve the asymptotic stability with asynchronous controller, a conditional probability is introduced to describe the asynchronism of system and controller modes, which is dependent on the active system mode. Besides, due to the difficulty in acquiring all the mode transition probabilities in practice, the transition probabilities of the Markovian jump system and the controllers are supposed to be partially unknown. A necessary and sufficient condition is developed to guarantee the stochastic stability of the resultant closed-loop system and further extended to asynchronous stabilization with partially known transition probabilities. Finally, the effectiveness and advantages of the proposed methods are demonstrated by two illustrative examples. 相似文献
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All existing works regarding the throughput of underwater acoustic networks (UWANs) explicitly ignore multipath effect of underwater acoustic channels (UWACs), which, however, is a prominent feature in underwater environments. In this paper, we investigate the throughput of UWANs with significant multipath delays. We extend the popular delay matrix model to make it suitable for analysis of throughput in UWANs with multipath delays. We differentiate between two cases of successful transmissions corresponding to different channel models. With the extended model, we derive the upper bounds of throughput for UWANs under different channel models with various fair constraints. We also show the necessary conditions for achieving these upper bounds under different scenarios. In addition, with derived upper bounds and necessary conditions, we offer designing rules for optimal schedules in UWANs with different channel models. Some examples of optimal schedules which could achieve the upper bounds under different scenarios are also provided. 相似文献
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中国共产党在执政的新阶段更为关注的和谐社会，其在理论与实践上不仅是唯物的，而且也是辩证的。这主要体现在和谐社会系统和其内部各要素辩证运动的过程中，而现阶段作为社会子系统的社会阶层结构的新变化及其影响必然会反作用于新时期和谐社会的构建之中。因此，适时、科学地研究我国阶层变迁给和谐社会构建带来的契机与挑战有着迫切的现实意义。 相似文献
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Evdokimova Olga L. Alves Carla S. Krsmanović Whiffen Radenka M. Ortega Zaida Tomás Helena Rodrigues João 《Journal of Zhejiang University. Science. B》2021,22(6):450-461
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications. 相似文献
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针对全球化时代的高等教育问题,分析基于全球胜任力的教学现状,根据教学实际问题,提出基于全球胜任力的教学目标,设计了C语言全英文课程在线教学体系。从全球胜任力的4个维度出发,介绍如何培养具备全球胜任力的领军人才。 相似文献
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对任意有限群G的整群环ZG,设Δn(G)是ZG的n次增广理想,记Qn(G)=Δn(G)/Δn 1(G)为G的增广商群.本文给出了Qn(G)的一组与G的Sylowp-子群相关的生成元,并且在利用这组生成元和已有结果的基础上对二面体群D2tk(k奇)之增广商群Qn(D2tk)的结构进行了讨论,证明了Qn(D2tk)Qn(D2t). 相似文献
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