由于认知无线电(Cognitive Radio,CR)网络允许多个未知无线设备接入频谱,使其存在模仿主用户攻击(Primary User Emulation Attack,PUEA)的安全隐患,为此,提出一种具有攻击感知能力的协作感知方案.首先,在授权主用户信号频谱资源处于占...由于认知无线电(Cognitive Radio,CR)网络允许多个未知无线设备接入频谱,使其存在模仿主用户攻击(Primary User Emulation Attack,PUEA)的安全隐患,为此,提出一种具有攻击感知能力的协作感知方案.首先,在授权主用户信号频谱资源处于占用和空闲这2种情况下,估计PUEA伪信号出现的概率;然后,利用得到的估计参数确定最小化总误差概率的最优阈值;最后,融合中心通过感知报告与阈值来判断主用户信号是否存在,以达到感知模仿主用户攻击的能力.仿真试验结果表明:与最优用户选择(Optimal User Selection,OUS)方法相比,提出的方法在应对主用户仿真攻击时具有更好的安全性能,提高了CR网络的安全效能.展开更多
Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is ina...Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is inaccurate and the operating conditions are uncertain. Based on the proportional navigation, the fuzzy logic and the genetic algorithm are combined to develop an evolutionary fuzzy navigation law with self-adapt region for the air-to-air missile guidance. The line of sight (LOS) rate and the closing speed between the missile and the target are inputs of the fuzzy controller. The output of the fuzzy controller is the commanded acceleration. Then a nonlinear function based on the conventional fuzzy logic control is imported to change the region. This nonlinear function can be changed with the input variables. So the dynamic change of the fuzzy variable region is achieved. The guidance law is optimized by the genetic algorithm. Simulation results of air-to-air missile attack using MATLAB show that the method needs less acceleration and shorter flying time, and its realization is simple.[KH*3/4D]展开更多
Prior group-based fingerprinting achieves better detection performance when colluders are from the same group. But in digital wholesale and needs to be identified retail, the middleman as well as customers especially ...Prior group-based fingerprinting achieves better detection performance when colluders are from the same group. But in digital wholesale and needs to be identified retail, the middleman as well as customers especially against group colluding attack. The group tracing is neglected in previous works. In this paper, we propose a novel multimedia group fingerprint to trace malicious middlemen along with customers. We explore the quality of the non degenerate linear shift register sequence （NDLSRS） which is convenient in group initialization and management. The theoretic analysis and simulation experiment results show that NDLSRS has good resistance against attacks from colluding groups/ members even after its volume expanded.展开更多
文摘由于认知无线电(Cognitive Radio,CR)网络允许多个未知无线设备接入频谱,使其存在模仿主用户攻击(Primary User Emulation Attack,PUEA)的安全隐患,为此,提出一种具有攻击感知能力的协作感知方案.首先,在授权主用户信号频谱资源处于占用和空闲这2种情况下,估计PUEA伪信号出现的概率;然后,利用得到的估计参数确定最小化总误差概率的最优阈值;最后,融合中心通过感知报告与阈值来判断主用户信号是否存在,以达到感知模仿主用户攻击的能力.仿真试验结果表明:与最优用户选择(Optimal User Selection,OUS)方法相比,提出的方法在应对主用户仿真攻击时具有更好的安全性能,提高了CR网络的安全效能.
文摘Effective guidance is one of the most important tasks to the performance of air-to-air missile. The fuzzy logic controller is able to perform effectively even in situations where the information about the plant is inaccurate and the operating conditions are uncertain. Based on the proportional navigation, the fuzzy logic and the genetic algorithm are combined to develop an evolutionary fuzzy navigation law with self-adapt region for the air-to-air missile guidance. The line of sight (LOS) rate and the closing speed between the missile and the target are inputs of the fuzzy controller. The output of the fuzzy controller is the commanded acceleration. Then a nonlinear function based on the conventional fuzzy logic control is imported to change the region. This nonlinear function can be changed with the input variables. So the dynamic change of the fuzzy variable region is achieved. The guidance law is optimized by the genetic algorithm. Simulation results of air-to-air missile attack using MATLAB show that the method needs less acceleration and shorter flying time, and its realization is simple.[KH*3/4D]
文摘Prior group-based fingerprinting achieves better detection performance when colluders are from the same group. But in digital wholesale and needs to be identified retail, the middleman as well as customers especially against group colluding attack. The group tracing is neglected in previous works. In this paper, we propose a novel multimedia group fingerprint to trace malicious middlemen along with customers. We explore the quality of the non degenerate linear shift register sequence （NDLSRS） which is convenient in group initialization and management. The theoretic analysis and simulation experiment results show that NDLSRS has good resistance against attacks from colluding groups/ members even after its volume expanded.
