融合自适应周期与兴趣量因子的轻量级GCN推荐

推荐系统在成熟的数据挖掘技术推动下,已能高效地利用评分数据、行为轨迹等显隐性信息,再与复杂而先进的深度学习技术相结合,取得了很好的效果.同时,其应用需求也驱动着对基础数据的深度挖掘与利用,以及对技术要求的减负成为一个研究热点.基于此,提出一种利用GCN(graph convolutional network)方法进行深度信息融合的轻量级推荐模型LG_APIF.该模型结合行为记忆,通过艾宾浩斯遗忘曲线模拟用户兴趣变化过程,采用线性回归等相对轻量的传统方法挖掘项目的自适应周期等深度信息;分析用户当前的兴趣分布,计算项目的兴趣量,以获取用户的潜在兴趣类型;构建用户-类型-项目三元组的图结构,并结合减负后的GCN技术来生成最终的项目推荐列表.实验验证所提方法的有效性,通过与8个经典模型在Last.fm,Douban,Yelp,MovieLens数据集中的对比,表明该方法在Precision,Recall及NDCG指标上都得到良好改善,其中,Precision平均提升2.11%,Recall平均提升1.01%,NDCG平均提升1.48%.

多视角融合的时空动态GCN城市交通流量预测

城市交通流量预测是构建绿色低碳、安全高效的智能交通系统的重要组成部分.时空图神经网络由于具有强大的时空数据表征能力,被广泛应用于城市交通流量预测.当前,时空图神经网络在城市交通流量预测中仍存在以下两方面局限性:1)直接构建静态路网拓扑图对城市空间相关性进行表示,忽略了节点的动态交通模式,难以表达节点流量之间的时序相似性,无法捕获路网节点之间在时序上的动态关联;2)只考虑路网节点的局部空间相关性,忽略节点的全局空间相关性,无法建模交通路网中局部区域和全局空间之间的依赖关系.为打破上述局限性,提出了一种多视角融合的时空动态图卷积模型用于预测交通流量:首先,从静态空间拓扑和动态流量模式视角出发,构建路网空间结构图和动态流量关联图,并使用动态图卷积学习节点在两种视角下的特征,全面捕获城市路网中多元的空间相关性;其次,从局部视角和全局视角出发,计算路网的全局表示,将全局特征与局部特征融合,增强路网节点特征的表现力,发掘城市交通流量的整体结构特征;接下来,设计了局部卷积多头自注意力机制来获取交通数据的动态时间相关性,实现在多种时间窗口下的准确流量预测;最后,在4种真实交通数据上的实验结果,证明了该模型的有效性和准确性.

Attack Behavior Extraction Based on Heterogeneous Cyberthreat Intelligence and Graph Convolutional Networks

The continuous improvement of the cyber threat intelligence sharing mechanism provides new ideas to deal with Advanced Persistent Threats(APT).Extracting attack behaviors,i.e.,Tactics,Techniques,Procedures(TTP)from Cyber Threat Intelligence(CTI)can facilitate APT actors’profiling for an immediate response.However,it is difficult for traditional manual methods to analyze attack behaviors from cyber threat intelligence due to its heterogeneous nature.Based on the Adversarial Tactics,Techniques and Common Knowledge(ATT&CK)of threat behavior description,this paper proposes a threat behavioral knowledge extraction framework that integrates Heterogeneous Text Network(HTN)and Graph Convolutional Network(GCN)to solve this issue.It leverages the hierarchical correlation relationships of attack techniques and tactics in the ATT&CK to construct a text network of heterogeneous cyber threat intelligence.With the help of the Bidirectional EncoderRepresentation fromTransformers(BERT)pretraining model to analyze the contextual semantics of cyber threat intelligence,the task of threat behavior identification is transformed into a text classification task,which automatically extracts attack behavior in CTI,then identifies the malware and advanced threat actors.The experimental results show that F1 achieve 94.86%and 92.15%for the multi-label classification tasks of tactics and techniques.Extend the experiment to verify the method’s effectiveness in identifying the malware and threat actors in APT attacks.The F1 for malware and advanced threat actors identification task reached 98.45%and 99.48%,which are better than the benchmark model in the experiment and achieve state of the art.The model can effectivelymodel threat intelligence text data and acquire knowledge and experience migration by correlating implied features with a priori knowledge to compensate for insufficient sample data and improve the classification performance and recognition ability of threat behavior in text.

A malware propagation prediction model based on representation learning and graph convolutional networks

The traditional malware research is mainly based on its recognition and detection as a breakthrough point,without focusing on its propagation trends or predicting the subsequently infected nodes.The complexity of network structure,diversity of network nodes,and sparsity of data all pose difficulties in predicting propagation.This paper proposes a malware propagation prediction model based on representation learning and Graph Convolutional Networks(GCN)to address the aforementioned problems.First,to solve the problem of the inaccuracy of infection intensity calculation caused by the sparsity of node interaction behavior data in the malware propagation network,a mechanism based on a tensor to mine the infection intensity among nodes is proposed to retain the network structure information.The influence of the relationship between nodes on the infection intensity is also analyzed.Second,given the diversity and complexity of the content and structure of infected and normal nodes in the network,considering the advantages of representation learning in data feature extraction,the corresponding representation learning method is adopted for the characteristics of infection intensity among nodes.This can efficiently calculate the relationship between entities and relationships in low dimensional space to achieve the goal of low dimensional,dense,and real-valued representation learning for the characteristics of propagation spatial data.We also design a new method,Tensor2vec,to learn the potential structural features of malware propagation.Finally,considering the convolution ability of GCN for non-Euclidean data,we propose a dynamic prediction model of malware propagation based on representation learning and GCN to solve the time effectiveness problem of the malware propagation carrier.The experimental results show that the proposed model can effectively predict the behaviors of the nodes in the network and discover the influence of different characteristics of nodes on the malware propagation situation.

Micro-expression recognition algorithm based on graph convolutional network and Transformer model

Micro-expressions are spontaneous, unconscious movements that reveal true emotions.Accurate facial movement information and network training learning methods are crucial for micro-expression recognition.However, most existing micro-expression recognition technologies so far focus on modeling the single category of micro-expression images and neural network structure.Aiming at the problems of low recognition rate and weak model generalization ability in micro-expression recognition, a micro-expression recognition algorithm is proposed based on graph convolution network(GCN) and Transformer model.Firstly, action unit(AU) feature detection is extracted and facial muscle nodes in the neighborhood are divided into three subsets for recognition.Then, graph convolution layer is used to find the layout of dependencies between AU nodes of micro-expression classification.Finally, multiple attentional features of each facial action are enriched with Transformer model to include more sequence information before calculating the overall correlation of each region.The proposed method is validated in CASME II and CAS(ME)^2 datasets, and the recognition rate reached 69.85%.

基于GCN和QP的智能车辆换道决策规划

考虑动态驾驶场景下车辆间的交互影响,提出了一种基于图卷积网络和二次规划的智能车辆自主换道行为决策与运动规划方法.首先将感兴趣区域进行分层建模,以图结构数据的形式对驾驶场景的全局和局部动态交互信息进行聚合,通过图卷积网络输出自车应采取的驾驶行为决策指令,然后与运动规划模块结合,基于局部子图划分可通行区域,构建并求解二次规划模型,得到满足运动学约束的无碰撞运动轨迹,最终完成无碰撞自主换道.对提出的方法进行了仿真实验与实车验证,实验结果证明该方法的性能要优于传统的规划方法,具有更好的实验成功率以及场景泛化性能.

CINO-TextGCN:融合CINO与TextGCN的藏文文本分类模型研究

为提高藏文新闻文本分类准确性,文章提出一种融合少数民族语言预训练模型(Chinese Minority Pr-etrained Language Model,CINO)和图卷积神经网络模型(Text Graph Convolutional Networks,TextGCN)的方法,即CINO-TextGCN模型。为有效评测该模型对藏文文本的分类性能,自建了较大规模和较高质量的藏文新闻文本公开数据集TNEWS(https://github.com/LG2016/CINO-TextGCN),通过实验发现,CINO-Text-GCN在公开数据集TNCC上的准确率为74.20%,在TNEWS上为83.96%。因此,该融合模型能够较好地捕捉到藏文文本语义,提升藏文文本分类性能。

基于改进GCN-sbuLSTM模型的高速公路交通量预测方法

为解决现有高速公路交通量预测方法在捕捉动态时空依赖关系方面的不足,提出了一种融合信息几何方法与注意力机制的新型高速路网交通量预测模型。首先,利用信息几何方法量化ETC门架之间的动态数据分布差异。然后,利用注意力机制来捕获交通的动态空间依赖关系。最后,结合一种堆叠的双向递归层结构,提出了一种长时间跨度的并行子模型算法,即基于信息几何方法(Information Geometry)和注意力机制(Attention Mechanism)优化的图卷积神经网络(GCN)结合堆叠双向单向长短期记忆神经网络(sbuLSTM)的组合模型—IGAGCN-sbuLSTM。采用该模型对100多条路段、3000多处门架近7亿条高速公路ETC门架系统数据进行分析,结果显示:与LSTM、GCN、GCN-LSTM、ASTGCN等现有4种模型相比,在10 min时间尺度下,IGAGCN-sbuLSTM组合模型的平均绝对误差(MAE)分别降低了2.39,3.72,1.02,1.46,均方根误差(RMSE)分别降低了3.25,4.32,2.05,5.65,平均绝对百分比误差(MAPE)分别降低了5.49%,12.54%,1.56%,0.5%。研究表明,IGAGCN-sbuLSTM模型在预测精度和不同时间间隔的预测性能上均优于现有的单一捕获特性模型及其他常用的组合模型,可广泛应用于高速公路收费、车速等数据的预测分析。

基于ST-GCN的空中交通管制员不安全行为识别

为预防和监督空中交通管制(ATC)工作中的违章行为,利用智能视频分析技术,研究适用于管制员坐姿工作的不安全行为识别模型。首先,分析管制员不安全工作行为的隐蔽性特征,总结5种典型管制员不安全行为,包括伸懒腰、瞌睡、低头入睡、歪头入睡和半躺入睡,并构建管制员不安全工作状态视频数据集(CUWS);其次,提出一种能描述管制员坐姿的骨架关键点拓展算法,基于时空图卷积网络(ST-GCN)搭建适用于管制员坐姿与腿部遮蔽情况下的不安全行为识别模型ATC-ST-GCN,并给出管制员不安全行为识别的工作流程;最后,利用CUWS数据集进行ATC-ST-GCN模型的训练和测试,并利用管制室实际监控视频开展验证试验。结果表明:该模型能够在有限验证数据集上实现5种典型不安全行为识别,准确率达到93.65%。试验结果证明该模型具有一定的科学性与有效性。

基于Vocab-GCN的中文医疗文本分类方法

提出一种应用于中文医疗文本分类的基于词汇级的图卷积神经网络(Vocab-GCN)模型。该模型不仅可以直接对医学文本关系图进行学习,在图嵌入中保存关系图的全局结构信息,得到含有语义网络的深层病理关系,而且仅依靠两层卷积神经网络(CNN)就展现出了良好的学习优势。实验结果表明:基于Vocab-GCN的中文医疗文本分类方法相比于最优的深度学习方法提高了6.17%的分类准确率,适用于患者初步对疾病类型做出诊断。

基于GCN-GRU组合模型的基坑周边管线沉降预测

为提高基坑变形预测结果的准确性,在传统的单点时间序列预测基础上,引入监测数据的空间特征对预测方法进行改进.基于图卷积神经网络(graph convolutional network,GCN)和门控循环单元(gate recurrent unit,GRU),构建一种能捕获数据时空关联性的变形预测模型GCN-GRU,并将其应用于上海某基坑周边管线沉降的变形预测.结果表明,相比于GRU时间序列预测模型,考虑了空间关联性的GCN-GRU模型在单步预测中的均方根误差(root mean square error,RMSE)和平均绝对百分比误差(mean absolute percentage error,MAPE)分别降低了27.3%和25.0%,多步预测中的RMSE和MAPE降低了37.2%和37.3%,预测结果准确性较高.该方法可为同类基坑工程周边管线沉降变形预测提供参考.

基于集成GCN-Transformer网络的ENSO预测模型

厄尔尼诺-南方涛动(El Niño-Southern Oscillation, ENSO)是热带太平洋海表面温度发生异常的现象,会导致冰雹、洪水、台风等极端天气的出现,因此对ENSO的准确预测意义重大。本文设计了集成GCN-Transformer(GCNTR)模型,首先运用Transformer网络的全局特征聚焦能力对数据特征进行编码,然后结合GCN提取图数据特征的能力,最后引入特征融合门控机制将经过编码的特征和GCN提取的特征进行融合,实现ENSO的精确预测。结果表明,GCNTR模型实现了对ENSO提前20个月的预测,比ENSOTR多了3个月,比Transformer多了5个月,并且模型绝大部分的预测精度优于其他模型。与现有的方法相比,GCNTR模型能够实现对ENSO更好的预测。

Sampling Methods for Efficient Training of Graph Convolutional Networks:A Survey

Graph convolutional networks(GCNs)have received significant attention from various research fields due to the excellent performance in learning graph representations.Although GCN performs well compared with other methods,it still faces challenges.Training a GCN model for large-scale graphs in a conventional way requires high computation and storage costs.Therefore,motivated by an urgent need in terms of efficiency and scalability in training GCN,sampling methods have been proposed and achieved a significant effect.In this paper,we categorize sampling methods based on the sampling mechanisms and provide a comprehensive survey of sampling methods for efficient training of GCN.To highlight the characteristics and differences of sampling methods,we present a detailed comparison within each category and further give an overall comparative analysis for the sampling methods in all categories.Finally,we discuss some challenges and future research directions of the sampling methods.

基于BERT-GCN的因果关系抽取

针对自然语言处理中传统因果关系抽取主要用基于模式匹配的方法或机器学习算法进行抽取,结果准确率较低,且只能抽取带有因果提示词的显性因果关系问题,提出一种使用大规模的预训练模型结合图卷积神经网络的算法BERT-GCN.首先,使用BERT(bidirectional encoder representation from transformers)对语料进行编码,生成词向量;然后,将生成的词向量放入图卷积神经网络中进行训练;最后,放入Softmax层中完成对因果关系的抽取.实验结果表明,该模型在数据集SEDR-CE上获得了较好的结果,且针对隐式的因果关系效果也较好.

Modeling Multi-Targets Sentiment Classification via Graph Convolutional Networks and Auxiliary Relation

Existing solutions do not work well when multi-targets coexist in a sentence.The reason is that the existing solution is usually to separate multiple targets and process them separately.If the original sentence has N target,the original sentence will be repeated for N times,and only one target will be processed each time.To some extent,this approach degenerates the fine-grained sentiment classification task into the sentence-level sentiment classification task,and the research method of processing the target separately ignores the internal relation and interaction between the targets.Based on the above considerations,we proposes to use Graph Convolutional Network(GCN)to model and process multi-targets appearing in sentences at the same time based on the positional relationship,and then to construct a graph of the sentiment relationship between targets based on the difference of the sentiment polarity between target words.In addition to the standard target-dependent sentiment classification task,an auxiliary node relation classification task is constructed.Experiments demonstrate that our model achieves new comparable performance on the benchmark datasets:SemEval-2014 Task 4,i.e.,reviews for restaurants and laptops.Furthermore,the method of dividing the target words into isolated individuals has disadvantages,and the multi-task learning model is beneficial to enhance the feature extraction ability and expression ability of the model.

基于ST-GCN警用巡逻机器人警情识别系统设计

针对现有警用巡逻机器人警情识别系统识别种类单一、识别率较低等问题,基于时空—图卷积网络(ST-GCN)和OpenPose算法的融合,面向跌倒(fall)、打砸(smash)和推搡(push)3种警情,设计了警用巡逻机器人警情识别系统。通过在真实场景测试,3种警情识别率分别为:跌倒85%,打砸80%,推搡83%;实时识别帧率为10 fps。实验结果表明:所设计的警情识别系统可以实现多种警情的实时、准确、可靠识别,具有较高的应用价值。

基于ResGCN-GRU的大气污染风险源识别

重污染天气是“十四五”时期大气污染治理的重点工作,在重污染天气时期对风险源进行精准识别,可以及时发出预警,做好环境污染治理,防止污染事件进一步加重.基于网格化监测技术获取的数据,本文提出一种结合残差网络(ResNet)、图卷积网络(GCN)和门控循环网络(GRU)的深度学习模型ResGCN-GRU,该模型主要应用于重污染天气时期识别风险源.重污染天气的风险源往往都是区域性的,具有明显的时空特征,因而本文先利用GCN网络提取监测点位之间的空间特征,同时利用ResNet解决多层GCN带来的过平滑以及梯度消失问题;再利用GRU提取风险源的时间特征,最后将全连接层融合的时空特征输入到Softmax激活函数得到二分类概率值,再根据概率值得到分类结果.为验证本文提出的模型性能,本文基于沈阳市72个监测点位的数据,通过精确度、召回率以及综合评价指标对GCN、LSTM、GRU和GCN-GRU进行对比,实验结果表明ResGCN-GRU模型分类效果的精确度分别要好16.9%、4.3%、3.1%、2.9%,证明了本文提出的模型在大气风险源识别方面更加有效,可以根据风险源数据的时空特征达到对风险源的精准识别.

Heterogeneous graph construction and node representation learning method of Treatise on Febrile Diseases based on graph convolutional network

Objective To construct symptom-formula-herb heterogeneous graphs structured Treatise on Febrile Diseases(Shang Han Lun,《伤寒论》)dataset and explore an optimal learning method represented with node attributes based on graph convolutional network(GCN).Methods Clauses that contain symptoms,formulas,and herbs were abstracted from Treatise on Febrile Diseases to construct symptom-formula-herb heterogeneous graphs,which were used to propose a node representation learning method based on GCN−the Traditional Chinese Medicine Graph Convolution Network(TCM-GCN).The symptom-formula,symptom-herb,and formula-herb heterogeneous graphs were processed with the TCM-GCN to realize high-order propagating message passing and neighbor aggregation to obtain new node representation attributes,and thus acquiring the nodes’sum-aggregations of symptoms,formulas,and herbs to lay a foundation for the downstream tasks of the prediction models.Results Comparisons among the node representations with multi-hot encoding,non-fusion encoding,and fusion encoding showed that the Precision@10,Recall@10,and F1-score@10 of the fusion encoding were 9.77%,6.65%,and 8.30%,respectively,higher than those of the non-fusion encoding in the prediction studies of the model.Conclusion Node representations by fusion encoding achieved comparatively ideal results,indicating the TCM-GCN is effective in realizing node-level representations of heterogeneous graph structured Treatise on Febrile Diseases dataset and is able to elevate the performance of the downstream tasks of the diagnosis model.

基于ICRITIC-GCN的空战目标威胁评估

为研究解决空战目标威胁评估问题时目标属性复杂、数据非结构化等问题,提高评估效率,提出图卷积网络(graph convolutional network,GCN)的解决方法,并引入改进的指标相关性权重确定方法(improved criteria importance through intercriteria correlation,ICRITIC),构建了基于ICRITICGCN的目标威胁评估模型。针对战场威胁目标的空间拓扑性和属性复杂性,利用图卷积网络在处理非欧式数据时的优势进行学习训练;针对传统方法在属性权重时过于主观的问题,ICRITIC法考虑属性之间的关联性及属性的信息量,客观分配属性权重。仿真结果表示,该算法在解决多目标威胁评估问题时,在处理效率、准确率等方面均有所提升。

Topology and Semantic Information Fusion Classification Network Based on Hyperspectral Images of Chinese Herbs

Most methods for classifying hyperspectral data only consider the local spatial relation-ship among samples,ignoring the important non-local topological relationship.However,the non-local topological relationship is better at representing the structure of hyperspectral data.This paper proposes a deep learning model called Topology and semantic information fusion classification network(TSFnet)that incorporates a topology structure and semantic information transmis-sion network to accurately classify traditional Chinese medicine in hyperspectral images.TSFnet uses a convolutional neural network(CNN)to extract features and a graph convolution network(GCN)to capture potential topological relationships among different types of Chinese herbal medicines.The results show that TSFnet outperforms other state-of-the-art deep learning classification algorithms in two different scenarios of herbal medicine datasets.Additionally,the proposed TSFnet model is lightweight and can be easily deployed for mobile herbal medicine classification.