With the rapid development of global information and the increasing dependence on network for people, network security problems are becoming more and more serious. By analyzing the existing security assessment methods...With the rapid development of global information and the increasing dependence on network for people, network security problems are becoming more and more serious. By analyzing the existing security assessment methods, we propose a network security situation evaluation system based on modified D-S evidence theory is proposed. Firstly, we give a modified D-S evidence theory to improve the reliability and rationality of the fusion result and apply the theory to correlation analysis. Secondly, the attack successful support is accurately calculated by matching internal factors with external threats. Multi-module evaluation is established to comprehensively evaluate the situation of network security. Finally we use an example of actual network datasets to validate the network security situation evaluation system. The simulation result shows that the system can not only reduce the rate of false positives and false alarms, but also effectively help analysts comprehensively to understand the situation of network security.展开更多
A finite-difference time-domain algorithm was applied to solve Maxwell’s equations to obtain the redistribution of an electromagnetic plane wave in the vicinity of a trailing indent crack(TIC).The roles of five geome...A finite-difference time-domain algorithm was applied to solve Maxwell’s equations to obtain the redistribution of an electromagnetic plane wave in the vicinity of a trailing indent crack(TIC).The roles of five geometrical parameters playing in light intensification were calculated numerically under the irradiation of a 355-nm normal incidence laser.The results show that the light intensity enhancements between the nearest neighbor pits were remarkable,which may lead to damage.The calculated results reveal that the light intensity enhancement factor(LIEF)can be up to 11.2 when TIC is on the rear-surface.With the increase of the length as well as the depth of pits,LIEF increased.Conversely,with the increase of the axis of pits,LIEF gradually declined to a stable status.It was observed that there exists an optima width or gap,which enables LIEF to be increased dramatically and then decreased gently.By comparison,results suggest that the worst cases occur when the depth and the length are both very large,especially if the width equals to 2?and the gap equals the width.This work provides a recommended theoretical criterion for defect inspection and classification.展开更多
基金Supported by the Foundation of Tianjin for Science and Technology Innovation(10FDZDGX00400,11ZCKFGX00900)Key Project of Educational Reform Foundation of Tianjin Municipal Education Commission(C03-0809)
文摘With the rapid development of global information and the increasing dependence on network for people, network security problems are becoming more and more serious. By analyzing the existing security assessment methods, we propose a network security situation evaluation system based on modified D-S evidence theory is proposed. Firstly, we give a modified D-S evidence theory to improve the reliability and rationality of the fusion result and apply the theory to correlation analysis. Secondly, the attack successful support is accurately calculated by matching internal factors with external threats. Multi-module evaluation is established to comprehensively evaluate the situation of network security. Finally we use an example of actual network datasets to validate the network security situation evaluation system. The simulation result shows that the system can not only reduce the rate of false positives and false alarms, but also effectively help analysts comprehensively to understand the situation of network security.
基金supported by the Scientific Research Foundation for the Central Universities of China(Grant No.2014NZYQN14)
文摘A finite-difference time-domain algorithm was applied to solve Maxwell’s equations to obtain the redistribution of an electromagnetic plane wave in the vicinity of a trailing indent crack(TIC).The roles of five geometrical parameters playing in light intensification were calculated numerically under the irradiation of a 355-nm normal incidence laser.The results show that the light intensity enhancements between the nearest neighbor pits were remarkable,which may lead to damage.The calculated results reveal that the light intensity enhancement factor(LIEF)can be up to 11.2 when TIC is on the rear-surface.With the increase of the length as well as the depth of pits,LIEF increased.Conversely,with the increase of the axis of pits,LIEF gradually declined to a stable status.It was observed that there exists an optima width or gap,which enables LIEF to be increased dramatically and then decreased gently.By comparison,results suggest that the worst cases occur when the depth and the length are both very large,especially if the width equals to 2?and the gap equals the width.This work provides a recommended theoretical criterion for defect inspection and classification.
