HL-2M 实验网络与数据管理系统的设计与实现

HL-2M 网络与数据管理包含了实验网络系统、数据存储与备份系统,以及实验数据库与实验信息管 理系统等。实验网络系统是装置运行的支持骨架,为各子系统提供互联通道和信号传输能力;数据存储与备份系 统为托卡马克实验提供数据的存储管理与容灾备份服务;实验数据库系统为元数据与科学数据提供了高效的检 索、访问与管理;实验信息管理系统为装置各子系统提供了参数配置管理、运行日志记录与运行值守管理,实现 了实验运行管理信息化,提高了实验运行效率。     

新型大规模全光星形耦合器

提出了一种新型大规模全光星形耦合器。这种星形耦合器不但能提供巨大的端口数,而且由其构成的波分复用（WDM）星形网具有极大的组网灵活性,能方便地实现网络在线扩容,升级,满足未来超大规模双向波分复用网络系统的需求,同时也适用于目前广泛应用的单向波分复用网络系统。     

一类具有扇形死区的分数阶神经网络系统的模糊自适应同步

本文研究了一类具有扇形死区的分数阶神经网络系统的同步问题,提出了一种自适应模糊控制方法。首先,采用模糊逻辑系统对不确定的非线性函数进行逼近,通过分数阶自适应定律来更新模糊系统的参数。其次,基于分数阶李雅普诺夫稳定性准则,设计了一种自适应模糊变结构控制器,该控制器可以保证系统状态同步误差收敛到原点的足够小的邻域。最后,通过数值仿真验证本文方法的有效性。     

Attack Vulnerability of Network with Duplication-Divergence Mechanism

We study the attack vulnerability of network with duplication-divergence mechanism. Numerical results have shown that the duplication-divergence network with larger retention probability a is more robust against target attack relatively. Furthermore, duplication-divergence network is broken down more quickly than its counterpart BA network under target attack. Such result is consistent with the fact of WWW and Internet networks under target attack. So duplication-divergence model is a more realistic one for us to investigate the characteristics of the world wide web in future. We also observe that the exponent γ of degree distribution and average degree are important parameters of networks, reflecting the performance of networks under target attack. Our results are helpful to the research on the security of network.     

Controlling disease spread on networks with feedback mechanism

Many real-world networks have the ability to adapt themselves in response to the state of their nodes. This paper studies controlling disease spread on network with feedback mechanism, where the susceptible nodes are able to avoid contact with the infected ones by cutting their connections with probability when the density of infected nodes reaches a certain value in the network. Such feedback mechanism considers the networks' own adaptivity and the cost of immunization. The dynamical equations about immunization with feedback mechanism are solved and theoretical predictions are in agreement with the results of large scale simulations. It shows that when the lethality $\alpha$ increases, the prevalence decreases more greatly with the same immunization $g$. That is, with the same cost, a better controlling result can be obtained. This approach offers an effective and practical policy to control disease spread, and also may be relevant to other similar networks.     

光纤光栅多点传感的理论与实验研究

对光纤布拉格光栅多点传感进行了理论研究与实验研究。通过定义多点传感信号分辨因子,分析了探测器对传感信号的分辨条件,给出了多点温度与应变传感原理的数学表达式,并探讨了由光源带宽决定的系统实际复用能力。设计并实现了具有一定特色的光纤布拉格光栅多点传感网络系统,利用该系统对温度、位移进行了双路、多点传感实验分析与理论验证,实验结果与多点传感理论分析相符合。     

具有随机时延的模糊不确定网络控制系统的指数镇定

研究了一类非线性不确定网络系统的指数镇定问题.根据网络诱导时延在不同区间上取值,引入满足Bernoulli分布的随机变量,建立新的非线性网络系统模型.利用Lyapunov稳定性理论,以线性矩阵不等式形式给出系统均方指数镇定条件和模糊控制器设计策略.仿真算例说明了方法的有效性.     

OFDM-PON系统中一种抑制峰均功率比的安全算法

安全性低和较高的峰均功率比(PAPR)是正交频分复用无源光网络(OFDM-PON)系统所面临的主要挑战,为此提出一种基于二维混沌加密的选择性映射(SLM)方案。该方案利用二维Logistic映射分别产生随机交织器和相位序列对OFDM信号进行加扰,达到系统加密的同时降低PAPR的目的。仿真结果显示,与传统SLM算法和原始光OFDM(O-OFDM)信号相比,所提出的方案可分别获得0.5dB和3.8dB的PAPR抑制增益。实验证明,7Gbit/s 16QAM (Quadrature Amplitude Modulation)O-OFDM加密信号可通过25km标准单模光纤在强度调制/直接检测OFDM-PON系统中安全传输并且系统误码率性能得到改善。