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基于案例推理的入侵检测关联分析研究 总被引:1,自引:0,他引:1
针对基于规则和模型的入侵检测专家系统中难以建立和表达入侵检测规则的问题,利用基于案例推理(CBR)方法对知识要求的低依赖性,将它引入入侵检测(ID)领域,提出了基于案例推理的入侵检测关联分析(CBRIDRA)模型的框架,研究了系统各功能模块,并对其中攻击案例定义、攻击案例检索、攻击案例管理、专家知识系统等关键技术的解决思路和实现方法进行了讨论。 相似文献
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目前网络入侵检测系统中存在大量的Fuzzy性问题,通过对三I算法的分析,提出一个基于RM蕴涵算子的三I算法,并就FMP(fuzzy modus pronens)问题,运用该算法,研究基于多维多重以及多维多重规则时的解。该算法在研究入侵检测系统中结合特征知识库,提取入侵行为规则,抽象出入侵行为检测Fuzzy推理的一般性模型,给出了基于该模型算法的描述,并分析了算法的性能,在该算法中,应用的Fuzzy推理是基于RM算子的三I算法。 相似文献
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论文针对Windows下信息获取的特点,探讨了一种将Windows入侵检测信息向黑客特征映射的归一化方法,并利用神经网络进行推理,解决Windows入侵检测信息来自不同层面不好关联的问题,同时实现入侵检测的并行推理和不确定性推理。 相似文献
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本文首先指出了将Agent技术应用于入侵检测系统的优势,依据入侵检测系统的特点给出了主机的状态转换图,并提出了一个入侵检测模型,该模型的主机中有数据异常检测Agent、特征提取Agent、数据一致性检测Agent、完整性检测Agent以及日志处理,Agent通过学习机制建立行为库,对行为库里的信息进行推理获得入侵规则信息并将其加入到入侵规则库.最后用Aglet技术对该模型进行了仿真和实现,得出基于Agent的入侵检测技术具有较高的检测率及较低的误报率。 相似文献
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Rong Long Wang Zheng Tang Qi Ping Cao 《Neural Networks, IEEE Transactions on》2004,15(6):1458-1465
We present a gradient ascent learning method of the Hopfield neural network for bipartite subgraph problem. The method is intended to provide a near-optimum parallel algorithm for solving the bipartite subgraph problem. To do this we use the Hopfield neural network to get a near-maximum bipartite subgraph, and increase the energy by modifying weights in a gradient ascent direction of the energy to help the network escape from the state of the near-maximum bipartite subgraph to the state of the maximum bipartite subgraph or better one. A large number of instances are simulated to verify the proposed method with the simulation results showing that the solution quality is superior to that of best existing parallel algorithm. We also test the learning method on total coloring problem. The simulation results show that our method finds optimal solution in every test graph. 相似文献
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In this article we describe an important structure used to model causal theories and a related problem of great interest to semi-empirical scientists. A causal Bayesian network is a pair consisting of a directed acyclic graph (called a causal graph) that represents causal relationships and a set of probability tables, that together with the graph specify the joint probability of the variables represented as nodes in the graph. We briefly describe the probabilistic semantics of causality proposed by Pearl for this graphical probabilistic model, and how unobservable variables greatly complicate models and their application. A common question about causal Bayesian networks is the problem of identifying causal effects from nonexperimental data, which is called the identifability problem. In the basic version of this problem, a semi-empirical scientist postulates a set of causal mechanisms and uses them, together with a probability distribution on the observable set of variables in a domain of interest, to predict the effect of a manipulation on some variable of interest. We explain this problem, provide several examples, and direct the readers to recent work that provides a solution to the problem and some of its extensions. We assume that the Bayesian network structure is given to us and do not address the problem of learning it from data and the related statistical inference and testing issues. 相似文献
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等价类学习是贝叶斯网络结构学习的一个重要分支,而本质图是贝叶斯网络等价类的图形表示,是进行等价类学习的有力工具。针对求解贝叶斯网络结构本质图存在的繁琐问题,提出了一种构建贝叶斯网络本质图的组合算法。该算法从初始非循环有向图开始,对所有有向边进行排序,保持V-结构中的边不变,将不参与V-结构的有向边转化为无向边,依次根据三条规则判定各条无向边在本质图中的方向。给出了算法的理论证明,通过具体案例分析验证了算法的有效性。 相似文献
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针对推断网络(NBI)的二分图方法中只是考虑用户是否评价过项目,却没有利用用户评分高低这一局限性,提出基于偏好的推断网络(PNBI)推荐方法。该方法在推断网络的基础上,考虑单个用户对项目评分高低体现了该用户对项目的喜好程度,在“用户-项目”的资源分配过程中,将资源分配给评分值较大的评分项,该方法能克服NBI算法中无法使用低评分值数据的缺陷。考虑到数据的稀疏性问题,采用倒排表的方法来节省相似度的运算次数,加速算法。在MovieLens数据集上的实验表明, PNBI二分图推荐算法在准确率、覆盖率和召回率三个方面均优于NBI二分图推荐算法。 相似文献
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知识推理是解决知识图谱中知识缺失问题的重要方法,针对大规模知识图谱中知识推理方法仍存在可解释性差、推理准确率和效率偏低的问题,提出了一种将知识表示和深度强化学习相结合的方法RLPTransE。利用知识表示学习方法,将知识图谱映射到含有三元组语义信息的向量空间中,并在该空间中建立强化学习环境。通过单步择优策略网络和多步推理策略网络的训练,使强化学习智能体在与环境交互过程中,高效挖掘推理规则进而完成推理。在公开数据集上的实验结果表明,相比于其他先进方法,该方法在大规模数据集推理任务中取得更好的表现。 相似文献
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In this paper, we introduce a probabilistic modeling approach for addressing the problem of Web robot detection from Web-server access logs. More specifically, we construct a Bayesian network that classifies automatically access log sessions as being crawler- or human-induced, by combining various pieces of evidence proven to characterize crawler and human behavior. Our approach uses an adaptive-threshold technique to extract Web sessions from access logs. Then, we apply machine learning techniques to determine the parameters of the probabilistic model. The resulting classification is based on the maximum posterior probability of all classes given the available evidence. We apply our method to real Web-server logs and obtain results that demonstrate the robustness and effectiveness of probabilistic reasoning for crawler detection. 相似文献
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Yali LV Junzhong MIAO Jiye LIANG Ling CHEN Yuhua QIAN 《Frontiers of Computer Science》2021,15(6):156337
Node order is one of the most important factors in learning the structure of a Bayesian network (BN) for probabilistic reasoning. To improve the BN structure learning, we propose a node order learning algorithmbased on the frequently used Bayesian information criterion (BIC) score function. The algorithm dramatically reduces the space of node order and makes the results of BN learning more stable and effective. Specifically, we first find the most dependent node for each individual node, prove analytically that the dependencies are undirected, and then construct undirected subgraphs UG. Secondly, the UG- is examined and connected into a single undirected graph UGC. The relation between the subgraph number and the node number is analyzed. Thirdly, we provide the rules of orienting directions for all edges in UGC, which converts it into a directed acyclic graph (DAG). Further, we rank the DAG’s topology order and describe the BIC-based node order learning algorithm. Its complexity analysis shows that the algorithm can be conducted in linear time with respect to the number of samples, and in polynomial time with respect to the number of variables. Finally, experimental results demonstrate significant performance improvement by comparing with other methods. 相似文献
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The authors propose the first parallel improvement algorithm using the maximum neural network model for the bipartite subgraph problem. The goal of this NP-complete problem is to remove the minimum number of edges in a given graph such that the remaining graph is a bipartite graph. A large number of instances have been simulated to verify the proposed algorithm, with the simulation result showing that the algorithm finds a solution within 200 iteration steps and the solution quality is superior to that of the best existing algorithm. The algorithm is extended for the K-partite subgraph problem where no algorithm has been proposed. 相似文献
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Qiang Jiao Hongwei Zhang Shengyuan Xu Frank L. Lewis Lihua Xie 《International journal of control》2013,86(12):2963-2972
In this paper, we consider bipartite tracking of linear multi-agent systems with a leader. Both homogeneous and heterogeneous systems are investigated. The communication between agents is modelled by a directed signed graph, where the negative (positive) edges represent the antagonistic (cooperative) interactions among agents. Linear Quadratic Regulator (LQR)-based approach is used to derive the distributed protocol for the follower agent to achieve bipartite tracking of the leader. It is shown that solving the bipartite tracking problem over the structurally balanced signed graph is equivalent to solving the cooperative tracking problem over a corresponding graph with nonnegative edge weights. This bridges the gap between the newly raised bipartite tracking problem and the well-studied cooperative tracking problem. Three novel control protocols are proposed for both cooperative and bipartite output tracking of heterogeneous linear multi-agent systems. Numerical examples are given to show the effectiveness of our control protocols. 相似文献