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Application of Self-Organizing Feature Map Neural Network Based on K-means Clustering in Network Intrusion Detection 被引量:5
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作者 Ling Tan Chong Li +1 位作者 Jingming Xia Jun Cao 《Computers, Materials & Continua》 SCIE EI 2019年第7期275-288,共14页
Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one... Due to the widespread use of the Internet,customer information is vulnerable to computer systems attack,which brings urgent need for the intrusion detection technology.Recently,network intrusion detection has been one of the most important technologies in network security detection.The accuracy of network intrusion detection has reached higher accuracy so far.However,these methods have very low efficiency in network intrusion detection,even the most popular SOM neural network method.In this paper,an efficient and fast network intrusion detection method was proposed.Firstly,the fundamental of the two different methods are introduced respectively.Then,the selforganizing feature map neural network based on K-means clustering(KSOM)algorithms was presented to improve the efficiency of network intrusion detection.Finally,the NSLKDD is used as network intrusion data set to demonstrate that the KSOM method can significantly reduce the number of clustering iteration than SOM method without substantially affecting the clustering results and the accuracy is much higher than Kmeans method.The Experimental results show that our method can relatively improve the accuracy of network intrusion and significantly reduce the number of clustering iteration. 展开更多
关键词 K-means clustering self-organizing feature map neural network network security intrusion detection NSL-KDD data set
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Self-organizing feature map neural network classification of the ASTER data based on wavelet fusion 被引量:7
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作者 HASI Bagan MA Jianwen LI Qiqing HAN Xiuzhen LIU Zhili 《Science China Earth Sciences》 SCIE EI CAS 2004年第7期651-658,共8页
Most methods for classification of remote sensing data are based on the statistical parameter evaluation with the assumption that the samples obey the normal distribution. How-ever, more accurate classification result... Most methods for classification of remote sensing data are based on the statistical parameter evaluation with the assumption that the samples obey the normal distribution. How-ever, more accurate classification results can be obtained with the neural network method through getting knowledge from environments and adjusting the parameter (or weight) step by step by a specific measurement. This paper focuses on the double-layer structured Kohonen self-organizing feature map (SOFM), for which all neurons within the two layers are linked one another and those of the competition layers are linked as well along the sides. Therefore, the self-adapting learning ability is improved due to the effective competition and suppression in this method. The SOFM has become a hot topic in the research area of remote sensing data classi-fication. The Advanced Spaceborne Thermal Emission and Reflectance Radiometer (ASTER) is a new satellite-borne remote sensing instrument with three 15-m resolution bands and three 30-m resolution bands at the near infrared. The ASTER data of Dagang district, Tianjin Munici-pality is used as the test data in this study. At first, the wavelet fusion is carried out to make the spatial resolutions of the ASTER data identical; then, the SOFM method is applied to classifying the land cover types. The classification results are compared with those of the maximum likeli-hood method (MLH). As a consequence, the classification accuracy of SOFM increases about by 7% in general and, in particular, it is almost as twice as that of the MLH method in the town. 展开更多
关键词 classification WAVELET fusion self-organizing neural network feature map (SOFM) ASTER data.
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Morphological self-organizing feature map neural network with applications to automatic target recognition
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作者 张世俊 敬忠良 李建勋 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第1期12-15,共4页
The rotation invariant feature of the target is obtained using the multi-direction feature extraction property of the steerable filter. Combining the morphological operation top-hat transform with the self-organizing ... The rotation invariant feature of the target is obtained using the multi-direction feature extraction property of the steerable filter. Combining the morphological operation top-hat transform with the self-organizing feature map neural network, the adaptive topological region is selected. Using the erosion operation, the topological region shrinkage is achieved. The steerable filter based morphological self-organizing feature map neural network is applied to automatic target recognition of binary standard patterns and real world infrared sequence images. Compared with Hamming network and morphological shared-weight networks respectively, the higher recognition correct rate, robust adaptability, quick training, and better generalization of the proposed method are achieved. 展开更多
关键词 feature extraction Image processing neural networks Self organizing maps Signal filtering and prediction
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Waterlogging risk assessment based on self-organizing map(SOM)artificial neural networks:a case study of an urban storm in Beijing 被引量:4
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作者 LAI Wen-li WANG Hong-rui +2 位作者 WANG Cheng ZHANG Jie ZHAO Yong 《Journal of Mountain Science》 SCIE CSCD 2017年第5期898-905,共8页
Due to rapid urbanization, waterlogging induced by torrential rainfall has become a global concern and a potential risk affecting urban habitant's safety. Widespread waterlogging disasters haveoccurred almost annu... Due to rapid urbanization, waterlogging induced by torrential rainfall has become a global concern and a potential risk affecting urban habitant's safety. Widespread waterlogging disasters haveoccurred almost annuallyinthe urban area of Beijing, the capital of China. Based on a selforganizing map(SOM) artificial neural network(ANN), a graded waterlogging risk assessment was conducted on 56 low-lying points in Beijing, China. Social risk factors, such as Gross domestic product(GDP), population density, and traffic congestion, were utilized as input datasets in this study. The results indicate that SOM-ANNis suitable for automatically and quantitatively assessing risks associated with waterlogging. The greatest advantage of SOM-ANN in the assessment of waterlogging risk is that a priori knowledge about classification categories and assessment indicator weights is not needed. As a result, SOM-ANN can effectively overcome interference from subjective factors,producing classification results that are more objective and accurate. In this paper, the risk level of waterlogging in Beijing was divided into five grades. The points that were assigned risk grades of IV or Vwere located mainly in the districts of Chaoyang, Haidian, Xicheng, and Dongcheng. 展开更多
关键词 Waterlogging risk assessment self-organizing map(SOM) neural network Urban storm
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Enhanced Self-Organizing Map Neural Network for DNA Sequence Classification
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作者 Marghny Mohamed Abeer A. Al-Mehdhar +1 位作者 Mohamed Bamatraf Moheb R. Girgis 《Intelligent Information Management》 2013年第1期25-33,共9页
The artificial neural networks (ANNs), among different soft computing methodologies are widely used to meet the challenges thrown by the main objectives of data mining classification techniques, due to their robust, p... The artificial neural networks (ANNs), among different soft computing methodologies are widely used to meet the challenges thrown by the main objectives of data mining classification techniques, due to their robust, powerful, distributed, fault tolerant computing and capability to learn in a data-rich environment. ANNs has been used in several fields, showing high performance as classifiers. The problem of dealing with non numerical data is one major obstacle prevents using them with various data sets and several domains. Another problem is their complex structure and how hands to interprets. Self-Organizing Map (SOM) is type of neural systems that can be easily interpreted, but still can’t be used with non numerical data directly. This paper presents an enhanced SOM structure to cope with non numerical data. It used DNA sequences as the training dataset. Results show very good performance compared to other classifiers. For better evaluation both micro-array structure and their sequential representation as proteins were targeted as dataset accuracy is measured accordingly. 展开更多
关键词 BIOINFORMATICS Artificial neural networks self-organizing map CLASSIFICATION SEQUENCE ALIGNMENT
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Pattern recognition of messily grown nanowire morphologies applying multi-layer connected self-organized feature maps
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作者 Qing Liu Hejun Li +1 位作者 Yulei Zhang Zhigang Zhao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2019年第5期946-956,共11页
Multi-layer connected self-organizing feature maps(SOFMs) and the associated learning procedure were proposed to achieve efficient recognition and clustering of messily grown nanowire morphologies. The network is made... Multi-layer connected self-organizing feature maps(SOFMs) and the associated learning procedure were proposed to achieve efficient recognition and clustering of messily grown nanowire morphologies. The network is made up by several paratactic 2-D SOFMs with inter-layer connections. By means of Monte Carlo simulations, virtual morphologies were generated to be the training samples. With the unsupervised inner-layer and inter-layer learning, the neural network can cluster different morphologies of messily grown nanowires and build connections between the morphological microstructure and geometrical features of nanowires within. Then, the as-proposed networks were applied on recognitions and quantitative estimations of the experimental morphologies. Results show that the as-trained SOFMs are able to cluster the morphologies and recognize the average length and quantity of the messily grown nanowires within. The inter-layer connections between winning neurons on each competitive layer have significant influence on the relations between the microstructure of the morphology and physical parameters of the nanowires within. 展开更多
关键词 Artificial neural networks self-organizing feature maps MONTE Carlo simulation Pattern recognition Messily grown NANOWIRE MORPHOLOGIES
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Fast and Accurate Machine Learning Inverse Lithography Using Physics Based Feature Maps and Specially Designed DCNN
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作者 Xuelong Shi Yan Yan +4 位作者 Tao Zhou Xueru Yu Chen Li Shoumian Chen Yuhang Zhao 《Journal of Microelectronic Manufacturing》 2020年第4期51-58,共8页
Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challengin... Inverse lithography technology(ILT)is intended to achieve optimal mask design to print a lithography target for a given lithography process.Full chip implementation of rigorous inverse lithography remains a challenging task because of enormous computational resource requirements and long computational time.To achieve full chip ILT solution,attempts have been made by using machine learning techniques based on deep convolution neural network(DCNN).The reported input for such DCNN is the rasterized images of the lithography target;such pure geometrical input requires DCNN to possess considerable number of layers to learn the optical properties of the mask,the nonlinear imaging process,and the rigorous ILT algorithm as well.To alleviate the difficulties,we have proposed the physics based optimal feature vector design for machine learning ILT in our early report.Although physics based feature vector followed by feedforward neural network can provide the solution to machine learning ILT,the feature vector is long and it can consume considerable amount of memory resource in practical implementation.To improve the resource efficiency,we proposed a hybrid approach in this study by combining first few physics based feature maps with a specially designed DCNN structure to learn the rigorous ILT algorithm.Our results show that this approach can make machine learning ILT easy,fast and more accurate. 展开更多
关键词 Optimal feature maps inverse lithography technology(ILT) deep convolution neural network(DCNN).
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English-Chinese Neural Machine Translation Based on Self-organizing Mapping Neural Network and Deep Feature Matching
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作者 Shu Ma 《IJLAI Transactions on Science and Engineering》 2024年第3期1-8,共8页
The traditional Chinese-English translation model tends to translate some source words repeatedly,while mistakenly ignoring some words.Therefore,we propose a novel English-Chinese neural machine translation based on s... The traditional Chinese-English translation model tends to translate some source words repeatedly,while mistakenly ignoring some words.Therefore,we propose a novel English-Chinese neural machine translation based on self-organizing mapping neural network and deep feature matching.In this model,word vector,two-way LSTM,2D neural network and other deep learning models are used to extract the semantic matching features of question-answer pairs.Self-organizing mapping(SOM)is used to classify and identify the sentence feature.The attention mechanism-based neural machine translation model is taken as the baseline system.The experimental results show that this framework significantly improves the adequacy of English-Chinese machine translation and achieves better results than the traditional attention mechanism-based English-Chinese machine translation model. 展开更多
关键词 Chinese-English translation model self-organizing mapping neural network Deep feature matching Deep learning
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An Emotion Analysis Method Using Multi-Channel Convolution Neural Network in Social Networks 被引量:2
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作者 Xinxin Lu Hong Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第10期281-297,共17页
As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practica... As an interdisciplinary comprehensive subject involving multidisciplinary knowledge,emotional analysis has become a hot topic in psychology,health medicine and computer science.It has a high comprehensive and practical application value.Emotion research based on the social network is a relatively new topic in the field of psychology and medical health research.The text emotion analysis of college students also has an important research significance for the emotional state of students at a certain time or a certain period,so as to understand their normal state,abnormal state and the reason of state change from the information they wrote.In view of the fact that convolutional neural network cannot make full use of the unique emotional information in sentences,and the need to label a large number of highquality training sets for emotional analysis to improve the accuracy of the model,an emotional analysismodel using the emotional dictionary andmultichannel convolutional neural network is proposed in this paper.Firstly,the input matrix of emotion dictionary is constructed according to the emotion information,and the different feature information of sentences is combined to form different network input channels,so that the model can learn the emotion information of input sentences from various feature representations in the training process.Then,the loss function is reconstructed to realize the semi supervised learning of the network.Finally,experiments are carried on COAE 2014 and self-built data sets.The proposed model can not only extract more semantic information in emotional text,but also learn the hidden emotional information in emotional text.The experimental results show that the proposed emotion analysis model can achieve a better classification performance.Compared with the best benchmark model gram-CNN,the F1 value can be increased by 0.026 in the self-built data set,and it can be increased by 0.032 in the COAE 2014 data set. 展开更多
关键词 Emotion analysis model emotion dictionary convolution neural network semi supervised learning deep learning pooling feature feature mapping
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A NOVEL INTRUSION DETECTION MODE BASED ON UNDERSTANDABLE NEURAL NETWORK TREES 被引量:1
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作者 Xu Qinzhen Yang Luxi +1 位作者 Zhao Qiangfu He Zhenya 《Journal of Electronics(China)》 2006年第4期574-579,共6页
Several data mining techniques such as Hidden Markov Model (HMM), artificial neural network, statistical techniques and expert systems are used to model network packets in the field of intrusion detection. In this pap... Several data mining techniques such as Hidden Markov Model (HMM), artificial neural network, statistical techniques and expert systems are used to model network packets in the field of intrusion detection. In this paper a novel intrusion detection mode based on understandable Neural Network Tree (NNTree) is pre-sented. NNTree is a modular neural network with the overall structure being a Decision Tree (DT), and each non-terminal node being an Expert Neural Network (ENN). One crucial advantage of using NNTrees is that they keep the non-symbolic model ENN’s capability of learning in changing environments. Another potential advantage of using NNTrees is that they are actually “gray boxes” as they can be interpreted easily if the num-ber of inputs for each ENN is limited. We showed through experiments that the trained NNTree achieved a simple ENN at each non-terminal node as well as a satisfying recognition rate of the network packets dataset. We also compared the performance with that of a three-layer backpropagation neural network. Experimental results indicated that the NNTree based intrusion detection model achieved better performance than the neural network based intrusion detection model. 展开更多
关键词 Intrusion detection neural network Tree (NNTree) Expert neural network (ENN) Decision Tree (DT) self-organized feature learning
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Comparison of Electric Load Forecasting between Using SOM and MLP Neural Network 被引量:1
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作者 Sergio Valero Carolina Senabre +3 位作者 Miguel Lopez Juan Aparicio Antonio Gabaldon Mario Ortiz 《Journal of Energy and Power Engineering》 2012年第3期411-417,共7页
Electric load forecasting has been a major area of research in the last decade since the production of accurate short-term forecasts for electricity loads has proven to be a key to success for many of the decision mak... Electric load forecasting has been a major area of research in the last decade since the production of accurate short-term forecasts for electricity loads has proven to be a key to success for many of the decision makers in the energy sector, from power generation to operation of the system. The objective of this research is to analyze the capacity of the MLP (multilayer perceptron neural network) versus SOM (self-organizing map neural network) for short-term load forecasting. The MLP is one of the most commonly used networks. It can be used for classification problems, model construction, series forecasting and discrete control. On the other hand, the SOM is a type of artificial neural network that is trained using unsupervised data to produce a low-dimensional, discretized representation of an input space of training samples in a cell map. Historical data of real global load demand were used for the research. Both neural models provide good prediction results, but the results obtained with the SOM maps are markedly better Also the main advantage of SOM maps is that they reach good results as a network unsupervised. It is much easier to train and interpret the results. 展开更多
关键词 Short-term load forecasting SOM self-organizing map multilayer perceptron neural network electricity markets.
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3D Ice Shape Description Method Based on BLSOM Neural Network
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作者 ZHU Bailiu ZUO Chenglin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期70-80,共11页
When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes t... When checking the ice shape calculation software,its accuracy is judged based on the proximity between the calculated ice shape and the typical test ice shape.Therefore,determining the typical test ice shape becomes the key task of the icing wind tunnel tests.In the icing wind tunnel test of the tail wing model of a large amphibious aircraft,in order to obtain accurate typical test ice shape,the Romer Absolute Scanner is used to obtain the 3D point cloud data of the ice shape on the tail wing model.Then,the batch-learning self-organizing map(BLSOM)neural network is used to obtain the 2D average ice shape along the model direction based on the 3D point cloud data of the ice shape,while its tolerance band is calculated using the probabilistic statistical method.The results show that the combination of 2D average ice shape and its tolerance band can represent the 3D characteristics of the test ice shape effectively,which can be used as the typical test ice shape for comparative analysis with the calculated ice shape. 展开更多
关键词 icing wind tunnel test ice shape batch-learning self-organizing map neural network 3D point cloud
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自监督对比学习驱动的SMWRec多模态微地图个性化推荐方法
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作者 马文骏 闫浩文 +3 位作者 李精忠 王小龙 王卓 余懿韬 《地球信息科学学报》 北大核心 2026年第1期105-119,共15页
【目的】现有微地图推荐系统主要依赖用户与内容的历史交互行为,忽视了图像、文本等多模态信息间的协同特征,导致在用户偏好建模和内容理解方面存在表达能力弱、模态融合度低的问题。【方法】针对这一问题,本文提出一种融合自监督机制... 【目的】现有微地图推荐系统主要依赖用户与内容的历史交互行为,忽视了图像、文本等多模态信息间的协同特征,导致在用户偏好建模和内容理解方面存在表达能力弱、模态融合度低的问题。【方法】针对这一问题,本文提出一种融合自监督机制的多模态个性化推荐框架——SMWRec。该方法以图神经网络为主干,联合构建主监督任务与3类自监督对比学习任务。在特征层面,设计特征随机丢弃与特征掩码两种模态无关的数据增强策略,以增强模型对信息不完整与扰动的鲁棒性;在模态层面,引入模态对齐机制,在融合前构建图文语义空间的一致性约束机制。该方法通过最大化同一项目不同视图间的表示一致性、最小化不同项目间的干扰,有效提升了模态间的表达协调性与判别能力。【结果】实验在Movielens、TikTok、Kwai和Wemaps 4个包含图文信息的多模态数据集上开展,评估指标包括Recall@K与NDCG@K,结果显示,SMWRec在4个数据集上普遍优于各强基线;其中在Wemaps中,Recall@10与NDCG@10分别较最优基线提升31.48%和33.86%。【结论】消融与模态缺失实验表明,“先对齐后融合”与特征增强是性能提升的主要来源,并能在部分模态缺失情况下保持较高排序质量。综上,SMWRec有效缓解了稀疏与缺失导致的表征退化,兼具准确性与鲁棒性,为微地图推荐提供了可复现、可扩展的多模态范式。 展开更多
关键词 微地图推荐 多模态 图神经网络 自监督学习 对比学习 特征随机丢弃 特征掩码 模态对齐
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Application of self-organizing neural networks to classification of plant communities in Pangquangou Nature Reserve, North China 被引量:2
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作者 Jintun ZHANG Hongxiao YANG 《Frontiers in Biology》 CSCD 2008年第4期512-517,共6页
Vegetation classification is an important topic in plant ecology and many quantitative techniques for classification have been developed in the field.The artificial neural network is a comparatively new tool for data ... Vegetation classification is an important topic in plant ecology and many quantitative techniques for classification have been developed in the field.The artificial neural network is a comparatively new tool for data analysis.The self-organizing feature map(SOFM)is powerful tool for clustering analysis.SOFM has been applied to many research fields and it was applied to the classification of plant communities in the Pangquangou Nature Reserve in the present work.Pangquangou Nature Reserve,located at 37°20′–38°20′ N,110°18′–111°18′ E,is a part of the Luliang Mountain range.Eighty-nine samples(quadrats)of 10 m×10 m for forest,4 m×4 m for shrubland and 1 m×1 m for grassland along an elevation gradient,were set up and species data was recorded in each sample.After discussion of the mathematical algorism,clustering technique and the procedure of SOFM,the classification was carried out by using NNTool box in MATLAB(6.5).As a result,the 89 samples were clustered into 13 groups representing 13 types of plant communities.The characteristics of each community were described.The result of SOFM classification was identical to the result of fuzzy c-mean clustering and consistent with the distribution patterns of vegetation in the study area and shows significant ecological meanings.This suggests that SOFM may clearly describe the ecological relationships between plant communities and it is a very effective quantitative technique in plant ecology research. 展开更多
关键词 neural network self-organizing feature map VEGETATION quantitative classification
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An improved de-interleaving algorithm of radar pulses based on SOFM with self-adaptive network topology 被引量:2
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作者 JIANG Wen FU Xiongjun +1 位作者 CHANG Jiayun QIN Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第4期712-721,共10页
As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signal... As a core part of the electronic warfare(EW) system,de-interleaving is used to separate interleaved radar signals. As interleaved radar pulses become more complex and denser, intelligent classification of radar signals has become very important. The self-organizing feature map(SOFM) is an excellent artificial neural network, which has huge advantages in intelligent classification of complex data. However, the de-interleaving process based on SOFM is faced with the problems that the initialization of the map size relies on prior information and the network topology cannot be adaptively adjusted. In this paper, an SOFM with self-adaptive network topology(SANT-SOFM) algorithm is proposed to solve the above problems. The SANT-SOFM algorithm first proposes an adaptive proliferation algorithm to adjust the map size, so that the initialization of the map size is no longer dependent on prior information but is gradually adjusted with the input data. Then,structural optimization algorithms are proposed to gradually optimize the topology of the SOFM network in the iterative process,constructing an optimal SANT. Finally, the optimized SOFM network is used for de-interleaving radar signals. Simulation results show that SANT-SOFM could get excellent performance in complex EW environments and the probability of getting the optimal map size is over 95% in the absence of priori information. 展开更多
关键词 de-interleaving self-organizing feature map(SOFM) self-adaptive network topology(SANT)
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SELF-ORGANIZING MAP OF COMPLEX NETWORKS FOR COMMUNITY DETECTION 被引量:1
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作者 Zhenping LI Ruisheng WANG +1 位作者 Xiang-Sun ZHANG Luonan CHEN 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2010年第5期931-941,共11页
Detecting communities from complex networks is an important issue and has attracted attention of researchers in many fields. It is relevant to social tasks, biological inquiries, and technological problems since vario... Detecting communities from complex networks is an important issue and has attracted attention of researchers in many fields. It is relevant to social tasks, biological inquiries, and technological problems since various networks exist in these systems. This paper proposes a new self-organizing map (SOM) based approach to community detection. By adopting a new operation and a new weightupdating scheme, a complex network can be organized into dense subgraphs according to the topological connection of each node by the SOM algorithm. Extensive numerical experiments show that the performance of the SOM algorithm is good. It can identify communities more accurately than existing methods. This method can be used to detect communities not only in undirected networks, but also in directed networks and bipartite networks. 展开更多
关键词 Community detection complex network neural networks self-organizing map.
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Intelligent identification method and application of seismic faults based on a balanced classification network
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作者 Yang Jing Ding Ren-Wei +4 位作者 Wang Hui-Yong Lin Nian-Tian Zhao Li-Hong Zhao Shuo Zhang Yu-Jie 《Applied Geophysics》 SCIE CSCD 2022年第2期209-220,307,共13页
This study combined fault identification with a deep learning algorithm and applied a convolutional neural network(CNN)design based on an improved balanced crossentropy(BCE)loss function to address the low accuracy in... This study combined fault identification with a deep learning algorithm and applied a convolutional neural network(CNN)design based on an improved balanced crossentropy(BCE)loss function to address the low accuracy in the intelligent identification of seismic faults and the slow training speed of convolutional neural networks caused by unbalanced training sample sets.The network structure and optimal hyperparameters were determined by extracting feature maps layer by layer and by analyzing the results of seismic feature extraction.The BCE loss function was used to add the parameter which is the ratio of nonfaults to the total sample sets,thereby changing the loss function to find the reference of the minimum weight parameter and adjusting the ratio of fault to nonfault data.The method overcame the unbalanced number of sample sets and improved the iteration speed.After a brief training,the accuracy could reach more than 95%,and gradient descent was evident.The proposed method was applied to fault identification in an oilfield area.The trained model can predict faults clearly,and the prediction results are basically consistent with an actual case,verifying the effectiveness and adaptability of the method. 展开更多
关键词 convolutional neural network seismic fault identification balanced cross-entropy loss function feature map
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The novel hierarchical clustering approach using selforganizing map with optimum dimension selection
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作者 Kshitij Tripathi 《Health Care Science》 2024年第2期88-100,共13页
Introduction: Data clustering is an important field of machine learningthat has applicability in wide areas, like, business analysis, manufacturing,energy, healthcare, traveling, and logistics. A variety of clustering... Introduction: Data clustering is an important field of machine learningthat has applicability in wide areas, like, business analysis, manufacturing,energy, healthcare, traveling, and logistics. A variety of clusteringapplications have already been developed. Data clustering approachesbased on self-organizing map (SOM) generally use the map dimensions (ofthe grid) ranging from 2 × 2 to 8 × 8 (4–64 neurons [microclusters])without any explicit reason for using the particular dimension, andtherefore optimized results are not obtained. These algorithms use somesecondary approaches to map these microclusters into the lowerdimension (actual number of clusters), like, 2, 3, or 4, as the case maybe, based on the optimum number of clusters in the specific data set. Thesecondary approach, observed in most of the works, is not SOM and is analgorithm, like, cut tree or the other.Methods: In this work, the proposed approach will give an idea of how toselect the most optimal higher dimension of SOM for the given data set,and this dimension is again clustered into the lower actual dimension.Primary and secondary, both utilize the SOM to cluster the data anddiscover that the weight matrix of the SOM is very meaningful. Theoptimized two-dimensional configuration of SOM is not the same forevery data set, and this work also tries to discover this configuration.Results: The adjusted randomized index obtained on the Iris, Wine,Wisconsin diagnostic breast cancer, New Thyroid, Seeds, A1, Imbalance,Dermatology, Ecoli, and Ionosphere is, respectively, 0.7173, 0.9134,0.7543, 0.8041, 0.7781, 0.8907, 0.8755, 0.7543, 0.5013, and 0.1728, whichoutperforms all other results available on the web and when no reductionof attributes is done in this work.Conclusions: It is found that SOM is superior to or on par with otherclustering approaches, like, k-means or the other, and could be usedsuccessfully to cluster all types of data sets. Ten benchmark data sets fromdiverse domains like medical, biological, and chemical are tested in this work,including the synthetic data sets. 展开更多
关键词 artificial neural network CLUSTERING self-organizing map
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基于注意力机制和多尺度融合的人群计数网络 被引量:1
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作者 栾方军 龚琪 袁帅 《计算机工程》 北大核心 2025年第3期352-361,共10页
为了应对人群图像中尺度变化和背景干扰的问题,提出一种人群计数网络模型,旨在充分利用多尺度信息并降低背景噪声的影响。首先采用ConvNeXt作为主干网络,用于提取特征。其次为了有效融合不同层次的特征,提出多层次特征融合模块(MFFM),... 为了应对人群图像中尺度变化和背景干扰的问题,提出一种人群计数网络模型,旨在充分利用多尺度信息并降低背景噪声的影响。首先采用ConvNeXt作为主干网络,用于提取特征。其次为了有效融合不同层次的特征,提出多层次特征融合模块(MFFM),将主干网络中不同层次的特征进行跨尺度融合,融合后的特征包含了不同尺度的语义信息,可以更好地适应人群计数任务中的尺度变化问题。接着为了更好地解决人群计数中存在的挑战,设计一个多尺度注意力模块(MSAM),根据不同感受野的分支提取不同尺度的特征,利用选择性Kernel通道注意力(SKCA)缓解多列结构存在的特征相似问题,并将模块生成的注意力图反馈到对应的尺度特征中,以抑制背景的干扰。网络模型在ShanghaiTechA数据集中的平均绝对误差(MAE)和均方根误差(RMSE)分别达到了56.1和93.9;在ShanghaiTechB数据集中的MAE和RMSE分别达到了6.1和10.3;在UCF_CC_50数据集中的MAE和RMSE分别达到了174.9和252.7;在Mall数据集中的MAE和RMSE分别达到了1.42和1.85。在公开数据集上的实验结果表明,提出的网络模型与现有代表性的人群计数方法相比,在提升人群计数任务的准确性和鲁棒性方面均取得了明显进展。 展开更多
关键词 人群计数 多尺度特征融合 注意力机制 神经网络 密度图
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基于CNN和Transformer双流融合的人体姿态估计
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作者 李鑫 张丹 +2 位作者 郭新 汪松 陈恩庆 《计算机工程与应用》 北大核心 2025年第5期187-199,共13页
卷积神经网络(CNN)和Transformer模型在人体姿态估计中有着广泛应用,然而Transformer更注重捕获图像的全局特征,忽视了局部特征对于人体姿态细节的重要性,而CNN则缺乏Transformer的全局建模能力。为了充分利用CNN处理局部信息和Transfor... 卷积神经网络(CNN)和Transformer模型在人体姿态估计中有着广泛应用,然而Transformer更注重捕获图像的全局特征,忽视了局部特征对于人体姿态细节的重要性,而CNN则缺乏Transformer的全局建模能力。为了充分利用CNN处理局部信息和Transformer处理全局信息的优势,构建一种CNN-Transformer双流的并行网络架构来聚合丰富的特征信息。由于传统Transformer的输入需要将图片展平为多个patch,不利于提取对位置敏感的人体结构信息,因此将其多头注意力结构进行改进,使模型输入能够保持原始2D特征图的结构;同时提出特征耦合模块融合两个分支不同分辨率下的特征,最大限度地保留局部特征与全局特征;最后引入改进后的坐标注意力模块(coordinate attention),进一步提升网络的特征提取能力。在COCO和MPII数据集上的实验结果表明所提模型相对目前主流模型具有更高的检测精度,从而说明所提模型能够充分捕获并融合人体姿态中的局部和全局特征。 展开更多
关键词 卷积神经网络 TRANSFORMER 局部特征 全局特征 2D特征图 特征耦合
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