为深入分析恶意代码高层行为之间的逻辑关系,剖析恶意代码的工作机制,针对现有的基于语义的行为分析方法无法进一步抽象出更高层语义行为以及挖掘之间逻辑关系的缺陷,文中以行为事件为研究对象,提出了一种基于语义分析的恶意代码攻击图...为深入分析恶意代码高层行为之间的逻辑关系,剖析恶意代码的工作机制,针对现有的基于语义的行为分析方法无法进一步抽象出更高层语义行为以及挖掘之间逻辑关系的缺陷,文中以行为事件为研究对象,提出了一种基于语义分析的恶意代码攻击图生成方法。首先,借助MITRE ATT&CK模型,设计了一种新的恶意代码行为分析模型——m-ATT&CK(Malware-Adversarial Tactics,Techniques,and Common Knowledges),该模型由恶意代码、行为事件、攻击战术及其之间的联系构成;然后,提出了基于F-MWTO(Fuzzy Method of Window Then Occurrence)的近似模式匹配行为映射算法,实现了恶意代码行为信息到m-ATT&CK模型的映射,并构建了隐马尔可夫模型挖掘攻击战术序列;最后,定义了恶意代码语义级攻击图并设计了其生成算法,结合已识别出的行为事件,还原恶意代码高层行为的上下文语义信息,生成恶意代码语义级攻击图。实验结果表明,基于以上方法得到的语义级攻击图能够清晰地展现恶意代码的工作机制以及攻击意图。展开更多
Noise can induce inverse period-doubling transition and chaos. The effects of the colored noise on periodic orbits, of the different periodic sequences in the logistic map, are investigated. It is found that the dynam...Noise can induce inverse period-doubling transition and chaos. The effects of the colored noise on periodic orbits, of the different periodic sequences in the logistic map, are investigated. It is found that the dynamical behaviors of the orbits, induced by an exponentially correlated colored noise, are different in the mergence of transition, and the effects of the noise intensity on their dynamical behaviors are different from the effects of the correlation time of noise. Remarkably, the noise can induce new periodic orbits, namely, two new orbits emerge in the period-four sequence at the bifurcation parameter value μ = 3.5, four new orbits in the period-eight sequence at μ= 3.55, and three new orbits in the period-six sequence at μ = 3.846, respectively. Moreover, the dynamical behaviors of the new orbits clearly show the resonancelike response to the colored noise.展开更多
Let C be a nonempty bounded closed convex subset of a uniformly convex Banach space with a Fréchet differentiable norm, and G be a directed system , let T= {T t:t∈G} be asymptotically nonexpansive ty...Let C be a nonempty bounded closed convex subset of a uniformly convex Banach space with a Fréchet differentiable norm, and G be a directed system , let T= {T t:t∈G} be asymptotically nonexpansive type mappings on C . We give the weak convergence theorem of {T t:t∈G} in this paper.展开更多
In this paper,the author considers a class of complete noncompact Riemannian manifoldswhich satisfy certain conditions on Ricci curvature and volume comparison. It is shown thatany harmonic map with finite energy from...In this paper,the author considers a class of complete noncompact Riemannian manifoldswhich satisfy certain conditions on Ricci curvature and volume comparison. It is shown thatany harmonic map with finite energy from such a manifold M into a normal geodesic ball inanother manifold N must be asymptotically constant at the infinity of each large end of M. Arelated existence theorem for harmonic maps is established.展开更多
A modified mapping method is used to obtain variable separation solution with two arbitrary functions of the(2+1)-dimensional Broer-Kaup-Kupershmidt equation.Based on the variable separation solution and by selecting ...A modified mapping method is used to obtain variable separation solution with two arbitrary functions of the(2+1)-dimensional Broer-Kaup-Kupershmidt equation.Based on the variable separation solution and by selecting appropriate functions,we discuss the completely elastic head-on collision between two dromion-lattices,non-completely elastic "chase and collision" between two multi-dromion-pairs and completely non-elastic interaction phenomenon between anti-dromion and dromion-pair.展开更多
文摘为深入分析恶意代码高层行为之间的逻辑关系,剖析恶意代码的工作机制,针对现有的基于语义的行为分析方法无法进一步抽象出更高层语义行为以及挖掘之间逻辑关系的缺陷,文中以行为事件为研究对象,提出了一种基于语义分析的恶意代码攻击图生成方法。首先,借助MITRE ATT&CK模型,设计了一种新的恶意代码行为分析模型——m-ATT&CK(Malware-Adversarial Tactics,Techniques,and Common Knowledges),该模型由恶意代码、行为事件、攻击战术及其之间的联系构成;然后,提出了基于F-MWTO(Fuzzy Method of Window Then Occurrence)的近似模式匹配行为映射算法,实现了恶意代码行为信息到m-ATT&CK模型的映射,并构建了隐马尔可夫模型挖掘攻击战术序列;最后,定义了恶意代码语义级攻击图并设计了其生成算法,结合已识别出的行为事件,还原恶意代码高层行为的上下文语义信息,生成恶意代码语义级攻击图。实验结果表明,基于以上方法得到的语义级攻击图能够清晰地展现恶意代码的工作机制以及攻击意图。
基金Supported by the National Natural Science Foundation of China under Grant No.30600122GuangDong Provincial Natural Science Foundation under Grant No.06025073
文摘Noise can induce inverse period-doubling transition and chaos. The effects of the colored noise on periodic orbits, of the different periodic sequences in the logistic map, are investigated. It is found that the dynamical behaviors of the orbits, induced by an exponentially correlated colored noise, are different in the mergence of transition, and the effects of the noise intensity on their dynamical behaviors are different from the effects of the correlation time of noise. Remarkably, the noise can induce new periodic orbits, namely, two new orbits emerge in the period-four sequence at the bifurcation parameter value μ = 3.5, four new orbits in the period-eight sequence at μ= 3.55, and three new orbits in the period-six sequence at μ = 3.846, respectively. Moreover, the dynamical behaviors of the new orbits clearly show the resonancelike response to the colored noise.
文摘Let C be a nonempty bounded closed convex subset of a uniformly convex Banach space with a Fréchet differentiable norm, and G be a directed system , let T= {T t:t∈G} be asymptotically nonexpansive type mappings on C . We give the weak convergence theorem of {T t:t∈G} in this paper.
文摘In this paper,the author considers a class of complete noncompact Riemannian manifoldswhich satisfy certain conditions on Ricci curvature and volume comparison. It is shown thatany harmonic map with finite energy from such a manifold M into a normal geodesic ball inanother manifold N must be asymptotically constant at the infinity of each large end of M. Arelated existence theorem for harmonic maps is established.
基金Supported by the National Natural Science Foundation of China under Grant No. 11005092the Program for Innovative Research Team of Young Teachers under Grant No. 2009RC01Undergraduate Innovative Base of Zhejiang Agriculture and Forestry University,the Zhejiang Province Undergraduate Scientific and Technological Innovation Project under Grant No. 2012R412018
文摘A modified mapping method is used to obtain variable separation solution with two arbitrary functions of the(2+1)-dimensional Broer-Kaup-Kupershmidt equation.Based on the variable separation solution and by selecting appropriate functions,we discuss the completely elastic head-on collision between two dromion-lattices,non-completely elastic "chase and collision" between two multi-dromion-pairs and completely non-elastic interaction phenomenon between anti-dromion and dromion-pair.
