Data Fusion-based resilient control system under DoS attacks: A game theoretic approach

In this paper, the resilient control under the Denial-of-Service (DoS) attack is rebuilt within the framework of Joint Directors of Laboratories (JDL) data fusion model. The JDL data fusion process is characterized by the so-called Game-in-Game approach, where decisions are made at different layers. The interactions between different JDL levels are considered which take the form of Packet Delivery Rate of the communication channel. Some criterions to judge whether the cyber defense system is able to protect the underlying control system is provided. Finally, a numerical example is proposed to verify the validity of the proposed method.     

信息安全策略实施困难的原因与对策分析

随着企业生产规模的扩大,其所掌控的资产也越来越多。信息作为企业重要的资产,其安全性正得到越来越多的企业的关注,很多企业为了保证自身信息的安全与保密性,也制订了自身的信息安全策略。然而,很多企业的信息安全策略常常形同虚设,没有发挥其应有的作用,甚至存在着严重的漏洞,为企业的健康发展埋下了不小的隐患。笔者结合自身多年的工作经验,就企业信息安全策略实施过程中存在的问题进行分析,并针对性的提出几点对策,希望对相关人士能有所帮助。     

基于系统辨识的自适应控制技术的应用

介绍基于系统辨识的自适应控制系统模型在莱钢2#精炼炉合金下料系统中的应用,通过不断地调整控制过程中的参数值,使控制系统的瞬态响应过程达到最优,消除了生产过程中人为因素的影响,提高了生产的均一性和稳定性.     

Accelerating a Recurrent Neural Network to Finite-Time Convergence for Solving Time-Varying Sylvester Equation by Using a Sign-Bi-power Activation Function

Bartels–Stewart algorithm is an effective and widely used method with an O(n ³) time complexity for solving a static Sylvester equation. When applied to time-varying Sylvester equation, the computation burden increases intensively with the decrease of sampling period and cannot satisfy continuous realtime calculation requirements. Gradient-based recurrent neural network are able to solve the time-varying Sylvester equation in real time but there always exists an estimation error. In contrast, the recently proposed Zhang neural network has been proven to converge to the solution of the Sylvester equation ideally when time goes to infinity. However, this neural network with the suggested activation functions never converges to the desired value in finite time, which may limit its applications in realtime processing. To tackle this problem, a sign-bi-power activation function is proposed in this paper to accelerate Zhang neural network to finite-time convergence. The global convergence and finite-time convergence property are proven in theory. The upper bound of the convergence time is derived analytically. Simulations are performed to evaluate the performance of the neural network with the proposed activation function. In addition, the proposed strategy is applied to online calculating the pseudo-inverse of a matrix and nonlinear control of an inverted pendulum system. Both theoretical analysis and numerical simulations validate the effectiveness of proposed activation function.     

网络设备配置信息备份系统的设计与实现

提出了如何设计开发网络设备配置信息备份系统,实现各种网络设备配置信息的远程备份,并用VBScript语言进行了具体实现。     

通信企业计算机网络安全技术研究

文章主要阐述了计算机网络攻击和入侵的特点、方法以及其安全防范手段,并集中对目前计算机网络安全技术进行了研究.     

Small sample improvements in the threshold cointegration test using residual-based moving block bootstrap

A residual-based moving block bootstrap procedure for testing the null hypothesis of linear cointegration versus cointegration with threshold effects is proposed. When the regressors and errors of the models are serially and contemporaneously correlated, our test compares favourably with the Sup LM test proposed by Gonzalo and Pitarakis. Indeed, shortcomings of the former motivated the development of our test. The small sample performance of the bootstrap test is investigated by Monte Carlo simulations, and the results show that the test performs better than the Sup LM test.     

GML模式匹配技术研究

GML是基于XML的空间信息编码标准。GML模式匹配技术作为实现应用模式的集成与共享的关键技术,与GML解析机理和实现技术密切相关。本文详细介绍了关于GML模式匹配的概念;给出了匹配方法的步骤、算法及已所实现的模式匹配详细流程,包括语意与结构相似度判断以及权重的设置;最后,对匹配过程中包含的不确定因素进行了分析与讨论。     

液剂视频序列中运动异物的模糊自适应分割

运动异物的正确分割是实现液剂自动检测的关键.提出一种基于帧差图空间方差和方差梯度的液剂异物模糊自适应阈值分割算法.首先将4帧序列图像差分得到的2幅帧差图分为5×5的图像块,计算2幅帧差图对应图像块间的方差和方差梯度,并以两者的乘积构成新特征图;然后使用自适应阈值对新特征图进行运动异物分割和提取.为使阈值能够跟随图像块灰度变化,阈值的调整采用模糊推理依据方差和方差梯度变化自适应实现.实验及实际测试结果表明,该算法能够满足低对比度和局部光照变化的液剂异物实时检测要求,是一种实用有效的图像分割算法.