为解决直接有效的拒绝服务(Denial of Service,DOS)攻击已对网络的正常运行造成严重影响这一问题,文章利用着色Petri网对DOS攻击下信息系统防御流程进行建模和分析,建立DOS攻击下着色Petri网的信息系统防御模型。将DOS攻击下信息系统的...为解决直接有效的拒绝服务(Denial of Service,DOS)攻击已对网络的正常运行造成严重影响这一问题,文章利用着色Petri网对DOS攻击下信息系统防御流程进行建模和分析,建立DOS攻击下着色Petri网的信息系统防御模型。将DOS攻击下信息系统的平均失效率作为评估信息系统防御DOS攻击可靠性的指标,以评价信息系统的可靠性。经过仿真验证分析,证明所建模型在结构上无死锁、有界、竞争公平,能够为DOS攻击下信息系统的可靠性评估提供可靠的决策依据。展开更多
A two-stage state recognition method is proposed for asynchronous SSVEP(steady-state visual evoked potential) based brain-computer interface(SBCI) system.The two-stage method is composed of the idle state(IS) detectio...A two-stage state recognition method is proposed for asynchronous SSVEP(steady-state visual evoked potential) based brain-computer interface(SBCI) system.The two-stage method is composed of the idle state(IS) detection and control state(CS) discrimination modules.Based on blind source separation and continuous wavelet transform techniques,the proposed method integrates functions of multi-electrode spatial filtering and feature extraction.In IS detection module,a method using the ensemble IS feature is proposed.In CS discrimination module,the ensemble CS feature is designed as feature vector for control intent classification.Further,performance comparisons are investigated among our IS detection module and other existing ones.Also the experimental results validate the satisfactory performance of our CS discrimination module.展开更多
文摘为解决直接有效的拒绝服务(Denial of Service,DOS)攻击已对网络的正常运行造成严重影响这一问题,文章利用着色Petri网对DOS攻击下信息系统防御流程进行建模和分析,建立DOS攻击下着色Petri网的信息系统防御模型。将DOS攻击下信息系统的平均失效率作为评估信息系统防御DOS攻击可靠性的指标,以评价信息系统的可靠性。经过仿真验证分析,证明所建模型在结构上无死锁、有界、竞争公平,能够为DOS攻击下信息系统的可靠性评估提供可靠的决策依据。
基金National Natural Science Foundation of China(90820305,60775040)
文摘A two-stage state recognition method is proposed for asynchronous SSVEP(steady-state visual evoked potential) based brain-computer interface(SBCI) system.The two-stage method is composed of the idle state(IS) detection and control state(CS) discrimination modules.Based on blind source separation and continuous wavelet transform techniques,the proposed method integrates functions of multi-electrode spatial filtering and feature extraction.In IS detection module,a method using the ensemble IS feature is proposed.In CS discrimination module,the ensemble CS feature is designed as feature vector for control intent classification.Further,performance comparisons are investigated among our IS detection module and other existing ones.Also the experimental results validate the satisfactory performance of our CS discrimination module.