Event relation extraction plays a crucial role in constructing an event knowledge graph.However,current models only extract trigger words as event ontology representations,and do not consider node type during informat...Event relation extraction plays a crucial role in constructing an event knowledge graph.However,current models only extract trigger words as event ontology representations,and do not consider node type during information aggregation,resulting in low accuracy in event relation extraction.To address these challenges,we propose an event relation extraction model based on heterogeneous graph attention networks and event ontology direction induction.To enhance the completeness of event information,we incorporate argument role information,in addition to trigger words,into the input text.A novel heterogeneous graph attention framework is proposed to reasonably allocate weights to trigger words,argument roles,and text information,and then perform two levels of aggregation,node-level and semantic-level,in sequence.To improve the accuracy of event direction discrimination,we construct an event ontology subgraph that includes trigger words and arguments to aggregate complete event structure information during direction induction.Finally,we evaluate our model on three datasets,TimeBank-Dense,MATRES,and HiEve,and demonstrate that our model outperforms state-of-the-art models by 1.2%,0.5%,and 0.8%,respectively,in terms of the Micro-F1 score.Our proposed model provides a promising solution for event relation extraction and can be applied in various natural language processing applications.展开更多
Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security ...Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security issues have also been introduced along with the benefits,which put an obstruction to the deployment of SDN.One root cause of these issues lies in the limited resources and capability of devices involved in the SDN architecture,especially the hardware switches lied in the data plane.In this paper,we analyze the vulnerability of SDN and present two kinds of SDN-targeted attacks:1)data-to-control plane saturation attack which exhausts resources of all SDN components,including control plane,data plane,and the in-between downlink channel and 2)control plane reflection attack which only attacks the data plane and gets conducted in a more efficient and hidden way.Finally,we propose the corresponding defense frameworks to mitigate such attacks.展开更多
基金supported by the National Natural Science Foundation of China(No.62071240)the Innovation Program for Quantum Science and Technology(No.2021ZD0302901)+1 种基金the Natural Science Foundation of Jiangsu Province(Nos.BK20220804 and BK20231142)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions.
文摘Event relation extraction plays a crucial role in constructing an event knowledge graph.However,current models only extract trigger words as event ontology representations,and do not consider node type during information aggregation,resulting in low accuracy in event relation extraction.To address these challenges,we propose an event relation extraction model based on heterogeneous graph attention networks and event ontology direction induction.To enhance the completeness of event information,we incorporate argument role information,in addition to trigger words,into the input text.A novel heterogeneous graph attention framework is proposed to reasonably allocate weights to trigger words,argument roles,and text information,and then perform two levels of aggregation,node-level and semantic-level,in sequence.To improve the accuracy of event direction discrimination,we construct an event ontology subgraph that includes trigger words and arguments to aggregate complete event structure information during direction induction.Finally,we evaluate our model on three datasets,TimeBank-Dense,MATRES,and HiEve,and demonstrate that our model outperforms state-of-the-art models by 1.2%,0.5%,and 0.8%,respectively,in terms of the Micro-F1 score.Our proposed model provides a promising solution for event relation extraction and can be applied in various natural language processing applications.
基金supported in part by the National Key R&D Program of China under Grant No.2017YFB0801701the National Science Foundation of China under Grant No.61472213CERNET Innovation Project(NGII20160123)
文摘Software defined networking(SDN)has attracted significant attention from both academia and industry by its ability to reconfigure network devices with logically centralized applications.However,some critical security issues have also been introduced along with the benefits,which put an obstruction to the deployment of SDN.One root cause of these issues lies in the limited resources and capability of devices involved in the SDN architecture,especially the hardware switches lied in the data plane.In this paper,we analyze the vulnerability of SDN and present two kinds of SDN-targeted attacks:1)data-to-control plane saturation attack which exhausts resources of all SDN components,including control plane,data plane,and the in-between downlink channel and 2)control plane reflection attack which only attacks the data plane and gets conducted in a more efficient and hidden way.Finally,we propose the corresponding defense frameworks to mitigate such attacks.
