期刊文献+
共找到3,354篇文章
< 1 2 168 >
每页显示 20 50 100
User Churn Prediction Hierarchical Model Based on Graph Attention Convolutional Neural Networks
1
作者 Mei Miao Tang Miao Zhou Long 《China Communications》 SCIE CSCD 2024年第7期169-185,共17页
The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications ... The telecommunications industry is becoming increasingly aware of potential subscriber churn as a result of the growing popularity of smartphones in the mobile Internet era,the quick development of telecommunications services,the implementation of the number portability policy,and the intensifying competition among operators.At the same time,users'consumption preferences and choices are evolving.Excellent churn prediction models must be created in order to accurately predict the churn tendency,since keeping existing customers is far less expensive than acquiring new ones.But conventional or learning-based algorithms can only go so far into a single subscriber's data;they cannot take into consideration changes in a subscriber's subscription and ignore the coupling and correlation between various features.Additionally,the current churn prediction models have a high computational burden,a fuzzy weight distribution,and significant resource economic costs.The prediction algorithms involving network models currently in use primarily take into account the private information shared between users with text and pictures,ignoring the reference value supplied by other users with the same package.This work suggests a user churn prediction model based on Graph Attention Convolutional Neural Network(GAT-CNN)to address the aforementioned issues.The main contributions of this paper are as follows:Firstly,we present a three-tiered hierarchical cloud-edge cooperative framework that increases the volume of user feature input by means of two aggregations at the device,edge,and cloud layers.Second,we extend the use of users'own data by introducing self-attention and graph convolution models to track the relative changes of both users and packages simultaneously.Lastly,we build an integrated offline-online system for churn prediction based on the strengths of the two models,and we experimentally validate the efficacy of cloudside collaborative training and inference.In summary,the churn prediction model based on Graph Attention Convolutional Neural Network presented in this paper can effectively address the drawbacks of conventional algorithms and offer telecom operators crucial decision support in developing subscriber retention strategies and cutting operational expenses. 展开更多
关键词 cloud-edge cooperative framework GAT-CNN self-attention and graph convolution models subscriber churn prediction
下载PDF
LKPNR: Large Language Models and Knowledge Graph for Personalized News Recommendation Framework
2
作者 Hao Chen Runfeng Xie +4 位作者 Xiangyang Cui Zhou Yan Xin Wang Zhanwei Xuan Kai Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4283-4296,共14页
Accurately recommending candidate news to users is a basic challenge of personalized news recommendation systems.Traditional methods are usually difficult to learn and acquire complex semantic information in news text... Accurately recommending candidate news to users is a basic challenge of personalized news recommendation systems.Traditional methods are usually difficult to learn and acquire complex semantic information in news texts,resulting in unsatisfactory recommendation results.Besides,these traditional methods are more friendly to active users with rich historical behaviors.However,they can not effectively solve the long tail problem of inactive users.To address these issues,this research presents a novel general framework that combines Large Language Models(LLM)and Knowledge Graphs(KG)into traditional methods.To learn the contextual information of news text,we use LLMs’powerful text understanding ability to generate news representations with rich semantic information,and then,the generated news representations are used to enhance the news encoding in traditional methods.In addition,multi-hops relationship of news entities is mined and the structural information of news is encoded using KG,thus alleviating the challenge of long-tail distribution.Experimental results demonstrate that compared with various traditional models,on evaluation indicators such as AUC,MRR,nDCG@5 and nDCG@10,the framework significantly improves the recommendation performance.The successful integration of LLM and KG in our framework has established a feasible way for achieving more accurate personalized news recommendation.Our code is available at https://github.com/Xuan-ZW/LKPNR. 展开更多
关键词 Large language models news recommendation knowledge graphs(KG)
下载PDF
Model Agnostic Meta-Learning(MAML)-Based Ensemble Model for Accurate Detection of Wheat Diseases Using Vision Transformer and Graph Neural Networks
3
作者 Yasir Maqsood Syed Muhammad Usman +3 位作者 Musaed Alhussein Khursheed Aurangzeb Shehzad Khalid Muhammad Zubair 《Computers, Materials & Continua》 SCIE EI 2024年第5期2795-2811,共17页
Wheat is a critical crop,extensively consumed worldwide,and its production enhancement is essential to meet escalating demand.The presence of diseases like stem rust,leaf rust,yellow rust,and tan spot significantly di... Wheat is a critical crop,extensively consumed worldwide,and its production enhancement is essential to meet escalating demand.The presence of diseases like stem rust,leaf rust,yellow rust,and tan spot significantly diminishes wheat yield,making the early and precise identification of these diseases vital for effective disease management.With advancements in deep learning algorithms,researchers have proposed many methods for the automated detection of disease pathogens;however,accurately detectingmultiple disease pathogens simultaneously remains a challenge.This challenge arises due to the scarcity of RGB images for multiple diseases,class imbalance in existing public datasets,and the difficulty in extracting features that discriminate between multiple classes of disease pathogens.In this research,a novel method is proposed based on Transfer Generative Adversarial Networks for augmenting existing data,thereby overcoming the problems of class imbalance and data scarcity.This study proposes a customized architecture of Vision Transformers(ViT),where the feature vector is obtained by concatenating features extracted from the custom ViT and Graph Neural Networks.This paper also proposes a Model AgnosticMeta Learning(MAML)based ensemble classifier for accurate classification.The proposedmodel,validated on public datasets for wheat disease pathogen classification,achieved a test accuracy of 99.20%and an F1-score of 97.95%.Compared with existing state-of-the-art methods,this proposed model outperforms in terms of accuracy,F1-score,and the number of disease pathogens detection.In future,more diseases can be included for detection along with some other modalities like pests and weed. 展开更多
关键词 Wheat disease detection deep learning vision transformer graph neural network model agnostic meta learning
下载PDF
TG-SMR:AText Summarization Algorithm Based on Topic and Graph Models 被引量:1
4
作者 Mohamed Ali Rakrouki Nawaf Alharbe +1 位作者 Mashael Khayyat Abeer Aljohani 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期395-408,共14页
Recently,automation is considered vital in most fields since computing methods have a significant role in facilitating work such as automatic text summarization.However,most of the computing methods that are used in r... Recently,automation is considered vital in most fields since computing methods have a significant role in facilitating work such as automatic text summarization.However,most of the computing methods that are used in real systems are based on graph models,which are characterized by their simplicity and stability.Thus,this paper proposes an improved extractive text summarization algorithm based on both topic and graph models.The methodology of this work consists of two stages.First,the well-known TextRank algorithm is analyzed and its shortcomings are investigated.Then,an improved method is proposed with a new computational model of sentence weights.The experimental results were carried out on standard DUC2004 and DUC2006 datasets and compared to four text summarization methods.Finally,through experiments on the DUC2004 and DUC2006 datasets,our proposed improved graph model algorithm TG-SMR(Topic Graph-Summarizer)is compared to other text summarization systems.The experimental results prove that the proposed TG-SMR algorithm achieves higher ROUGE scores.It is foreseen that the TG-SMR algorithm will open a new horizon that concerns the performance of ROUGE evaluation indicators. 展开更多
关键词 Natural language processing text summarization graph model topic model
下载PDF
Application Research on Two-Layer Threat Prediction Model Based on Event Graph
5
作者 Shuqin Zhang Xinyu Su +2 位作者 Yunfei Han Tianhui Du Peiyu Shi 《Computers, Materials & Continua》 SCIE EI 2023年第12期3993-4023,共31页
Advanced Persistent Threat(APT)is now the most common network assault.However,the existing threat analysis models cannot simultaneously predict the macro-development trend and micro-propagation path of APT attacks.The... Advanced Persistent Threat(APT)is now the most common network assault.However,the existing threat analysis models cannot simultaneously predict the macro-development trend and micro-propagation path of APT attacks.They cannot provide rapid and accurate early warning and decision responses to the present system state because they are inadequate at deducing the risk evolution rules of network threats.To address the above problems,firstly,this paper constructs the multi-source threat element analysis ontology(MTEAO)by integrating multi-source network security knowledge bases.Subsequently,based on MTEAO,we propose a two-layer threat prediction model(TL-TPM)that combines the knowledge graph and the event graph.The macro-layer of TL-TPM is based on the knowledge graph to derive the propagation path of threats among devices and to correlate threat elements for threat warning and decision-making;The micro-layer ingeniously maps the attack graph onto the event graph and derives the evolution path of attack techniques based on the event graph to improve the explainability of the evolution of threat events.The experiment’s results demonstrate that TL-TPM can completely depict the threat development trend,and the early warning results are more precise and scientific,offering knowledge and guidance for active defense. 展开更多
关键词 Knowledge graph multi-source data fusion network security threat modeling event graph absorbing Markov chain threat propagation path
下载PDF
Construction and application of knowledge graph for grid dispatch fault handling based on pre-trained model
6
作者 Zhixiang Ji Xiaohui Wang +1 位作者 Jie Zhang Di Wu 《Global Energy Interconnection》 EI CSCD 2023年第4期493-504,共12页
With the construction of new power systems,the power grid has become extremely large,with an increasing proportion of new energy and AC/DC hybrid connections.The dynamic characteristics and fault patterns of the power... With the construction of new power systems,the power grid has become extremely large,with an increasing proportion of new energy and AC/DC hybrid connections.The dynamic characteristics and fault patterns of the power grid are complex;additionally,power grid control is difficult,operation risks are high,and the task of fault handling is arduous.Traditional power-grid fault handling relies primarily on human experience.The difference in and lack of knowledge reserve of control personnel restrict the accuracy and timeliness of fault handling.Therefore,this mode of operation is no longer suitable for the requirements of new systems.Based on the multi-source heterogeneous data of power grid dispatch,this paper proposes a joint entity–relationship extraction method for power-grid dispatch fault processing based on a pre-trained model,constructs a knowledge graph of power-grid dispatch fault processing and designs,and develops a fault-processing auxiliary decision-making system based on the knowledge graph.It was applied to study a provincial dispatch control center,and it effectively improved the accident processing ability and intelligent level of accident management and control of the power grid. 展开更多
关键词 Power-grid dispatch fault handling Knowledge graph Pre-trained model Auxiliary decision-making
下载PDF
GraphMLP-Mixer:基于图-多层感知机架构的高效多行为序列推荐方法
7
作者 卢晓凯 封军 +2 位作者 韩永强 王皓 陈恩红 《计算机研究与发展》 EI CSCD 北大核心 2024年第8期1917-1929,共13页
在多行为序列推荐领域,图神经网络(GNNs)虽被广泛应用,但存在局限性,如对序列间协同信号建模不足和处理长距离依赖性等问题.针对这些问题,提出了一种新的解决框架GraphMLP-Mixer.该框架首先构造全局物品图来增强模型对序列间协同信号的... 在多行为序列推荐领域,图神经网络(GNNs)虽被广泛应用,但存在局限性,如对序列间协同信号建模不足和处理长距离依赖性等问题.针对这些问题,提出了一种新的解决框架GraphMLP-Mixer.该框架首先构造全局物品图来增强模型对序列间协同信号的建模,然后将感知机-混合器架构与图神经网络结合,得到图-感知机混合器模型对用户兴趣进行充分挖掘.GraphMLP-Mixer具有2个显著优势:一是能够有效捕捉用户行为的全局依赖性,同时减轻信息过压缩问题;二是其时间与空间效率显著提高,其复杂度与用户交互行为的数量成线性关系,优于现有基于GNN多行为序列推荐模型.在3个真实的公开数据集上进行实验,大量的实验结果验证了GraphMLP-Mixer在处理多行为序列推荐问题时的有效性和高效性. 展开更多
关键词 多行为建模 序列推荐 图神经网络 MLP架构 全局物品图
下载PDF
Noncooperative Model Predictive Game With Markov Jump Graph
8
作者 Yang Xu Yuan Yuan +1 位作者 Zhen Wang Xuelong Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第4期931-944,共14页
In this paper,the distributed stochastic model predictive control(MPC)is proposed for the noncooperative game problem of the discrete-time multi-player systems(MPSs)with the undirected Markov jump graph.To reflect the... In this paper,the distributed stochastic model predictive control(MPC)is proposed for the noncooperative game problem of the discrete-time multi-player systems(MPSs)with the undirected Markov jump graph.To reflect the reality,the state and input constraints have been considered along with the external disturbances.An iterative algorithm is designed such that model predictive noncooperative game could converge to the socalledε-Nash equilibrium in a distributed manner.Sufficient conditions are established to guarantee the convergence of the proposed algorithm.In addition,a set of easy-to-check conditions are provided to ensure the mean-square uniform bounded stability of the underlying MPSs.Finally,a numerical example on a group of spacecrafts is studied to verify the effectiveness of the proposed method. 展开更多
关键词 Markov jump graph model predictive control(MPC) multi-player systems(MPSs) noncooperative game ε-Nash equilibrium
下载PDF
Micro-expression recognition algorithm based on graph convolutional network and Transformer model
9
作者 吴进 PANG Wenting +1 位作者 WANG Lei ZHAO Bo 《High Technology Letters》 EI CAS 2023年第2期213-222,共10页
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 ... 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%. 展开更多
关键词 micro-expression recognition graph convolutional network(GCN) action unit(AU)detection Transformer model
下载PDF
Weighted Forwarding in Graph Convolution Networks for Recommendation Information Systems
10
作者 Sang-min Lee Namgi Kim 《Computers, Materials & Continua》 SCIE EI 2024年第2期1897-1914,共18页
Recommendation Information Systems(RIS)are pivotal in helping users in swiftly locating desired content from the vast amount of information available on the Internet.Graph Convolution Network(GCN)algorithms have been ... Recommendation Information Systems(RIS)are pivotal in helping users in swiftly locating desired content from the vast amount of information available on the Internet.Graph Convolution Network(GCN)algorithms have been employed to implement the RIS efficiently.However,the GCN algorithm faces limitations in terms of performance enhancement owing to the due to the embedding value-vanishing problem that occurs during the learning process.To address this issue,we propose a Weighted Forwarding method using the GCN(WF-GCN)algorithm.The proposed method involves multiplying the embedding results with different weights for each hop layer during graph learning.By applying the WF-GCN algorithm,which adjusts weights for each hop layer before forwarding to the next,nodes with many neighbors achieve higher embedding values.This approach facilitates the learning of more hop layers within the GCN framework.The efficacy of the WF-GCN was demonstrated through its application to various datasets.In the MovieLens dataset,the implementation of WF-GCN in LightGCN resulted in significant performance improvements,with recall and NDCG increasing by up to+163.64%and+132.04%,respectively.Similarly,in the Last.FM dataset,LightGCN using WF-GCN enhanced with WF-GCN showed substantial improvements,with the recall and NDCG metrics rising by up to+174.40%and+169.95%,respectively.Furthermore,the application of WF-GCN to Self-supervised Graph Learning(SGL)and Simple Graph Contrastive Learning(SimGCL)also demonstrated notable enhancements in both recall and NDCG across these datasets. 展开更多
关键词 Deep learning graph neural network graph convolution network graph convolution network model learning method recommender information systems
下载PDF
FLOCKING OF A THERMODYNAMIC CUCKER-SMALE MODEL WITH LOCAL VELOCITY INTERACTIONS
11
作者 金春银 李双智 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期632-649,共18页
In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on pe... In this paper, we study the flocking behavior of a thermodynamic Cucker–Smale model with local velocity interactions. Using the spectral gap of a connected stochastic matrix, together with an elaborate estimate on perturbations of a linearized system, we provide a sufficient framework in terms of initial data and model parameters to guarantee flocking. Moreover, it is shown that the system achieves a consensus at an exponential rate. 展开更多
关键词 FLOCKING local interaction thermodynamical Cucker-Smale model stochastic matrix neighbor graph
下载PDF
Dynamics of Advantageous Mutant Spread in Spatial Death-Birth and Birth-Death Moran Models
12
作者 Jasmine Foo Einar Bjarki Gunnarsson +1 位作者 Kevin Leder David Sivakoff 《Communications on Applied Mathematics and Computation》 EI 2024年第1期576-604,共29页
The spread of an advantageous mutation through a population is of fundamental interest in population genetics. While the classical Moran model is formulated for a well-mixed population, it has long been recognized tha... The spread of an advantageous mutation through a population is of fundamental interest in population genetics. While the classical Moran model is formulated for a well-mixed population, it has long been recognized that in real-world applications, the population usually has an explicit spatial structure which can significantly influence the dynamics. In the context of cancer initiation in epithelial tissue, several recent works have analyzed the dynamics of advantageous mutant spread on integer lattices, using the biased voter model from particle systems theory. In this spatial version of the Moran model, individuals first reproduce according to their fitness and then replace a neighboring individual. From a biological standpoint, the opposite dynamics, where individuals first die and are then replaced by a neighboring individual according to its fitness, are equally relevant. Here, we investigate this death-birth analogue of the biased voter model. We construct the process mathematically, derive the associated dual process, establish bounds on the survival probability of a single mutant, and prove that the process has an asymptotic shape. We also briefly discuss alternative birth-death and death-birth dynamics, depending on how the mutant fitness advantage affects the dynamics. We show that birth-death and death-birth formulations of the biased voter model are equivalent when fitness affects the former event of each update of the model, whereas the birth-death model is fundamentally different from the death-birth model when fitness affects the latter event. 展开更多
关键词 Spatial death-birth models Spatial birth-death models Spatial evolutionary models Spatial cancer models Evolutionary graph theory Stochastic processes Biased voter model Dual process Fixation probability Shape theorem
下载PDF
Calculating real-time surface deformation for large active surface radio antennas using a graph neural network
13
作者 Zihan Zhang Qian Ye +2 位作者 Li Fu Qinghui Liu Guoxiang Meng 《Astronomical Techniques and Instruments》 CSCD 2024年第5期267-274,共8页
This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible f... This paper presents an innovative surrogate modeling method using a graph neural network to compensate for gravitational and thermal deformation in large radio telescopes.Traditionally,rapid compensation is feasible for gravitational deformation but not for temperature-induced deformation.The introduction of this method facilitates real-time calculation of deformation caused both by gravity and temperature.Constructing the surrogate model involves two key steps.First,the gravitational and thermal loads are encoded,which facilitates more efficient learning for the neural network.This is followed by employing a graph neural network as an end-to-end model.This model effectively maps external loads to deformation while preserving the spatial correlations between nodes.Simulation results affirm that the proposed method can successfully estimate the surface deformation of the main reflector in real-time and can deliver results that are practically indistinguishable from those obtained using finite element analysis.We also compare the proposed surrogate model method with the out-of-focus holography method and yield similar results. 展开更多
关键词 Large radio telescope Surface deformation Surrogate model graph neural network
下载PDF
A Reduced-Order Modeling of Multi-Port RC Networks by Means of Graph Partitioning 被引量:1
14
作者 杨华中 冒小建 +1 位作者 燕昭然 汪蕙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第10期1037-1040,共4页
A modified reduced-order method for RC networks which takes a division-and-conquest strategy is presented.The whole network is partitioned into a set of sub-networks at first,then each of them is reduced by Krylov sub... A modified reduced-order method for RC networks which takes a division-and-conquest strategy is presented.The whole network is partitioned into a set of sub-networks at first,then each of them is reduced by Krylov subspace techniques,and finally all the reduced sub-networks are incorporated together.With some accuracy,this method can reduce the number of both nodes and components of the circuit comparing to the traditional methods which usually only offer a reduced net with less nodes.This can markedly accelerate the sparse-matrix-based simulators whose performance is dominated by the entity of the matrix or the number of components of the circuits. 展开更多
关键词 INTERCONNECT reduced-order modeling graph partitioning Krylov subspace
下载PDF
基于Graph WaveNet模型的机场网络延误预测
15
作者 姜雨 戴垚宇 +2 位作者 刘振宇 吴薇薇 顾欣 《武汉理工大学学报(交通科学与工程版)》 2023年第5期775-780,共6页
文中提出一种基于深度Graph WaveNet(GWN)模型的机场网络延误预测方法,对机场网络整体建模,将其转换为图结构并对网络中所有机场进行离港航班多步延误预测.GWN模型融合时间和空间卷积网络,时间卷积层引入扩展因果卷积和门控机制提升模... 文中提出一种基于深度Graph WaveNet(GWN)模型的机场网络延误预测方法,对机场网络整体建模,将其转换为图结构并对网络中所有机场进行离港航班多步延误预测.GWN模型融合时间和空间卷积网络,时间卷积层引入扩展因果卷积和门控机制提升模型效率;空间卷积层采用双向卷积及自适应邻接矩阵充分挖掘延误信息的空间关联性.选择美国51个机场构建机场网络并进行延误预测分析.结果表明:GWN模型对机场未来3天离港航班准点率预测的平均绝对误差分别为4.718%、5.145%和5.240%,显著优于其它基线模型,且对不同量级机场均有稳定的预测表现,在多步预测上具有突出优势. 展开更多
关键词 航班延误预测 graph WaveNet模型 机场网络 深度学习
下载PDF
基于多特征融合的GraphHeat-ChebNet隧道形变预测模型
16
作者 熊安萍 李梦凡 龙林波 《重庆邮电大学学报(自然科学版)》 CSCD 北大核心 2023年第1期164-175,共12页
对隧道的形变进行预测是隧道结构异常检测的内容之一。为了充分挖掘形变特征的时空关联性,针对隧道内衬多个断面的形变同时预测,提出一种基于多特征融合的GraphHeat-ChebNet隧道形变预测模型。所提模型中利用GraphHeat和ChebNet这2种图... 对隧道的形变进行预测是隧道结构异常检测的内容之一。为了充分挖掘形变特征的时空关联性,针对隧道内衬多个断面的形变同时预测,提出一种基于多特征融合的GraphHeat-ChebNet隧道形变预测模型。所提模型中利用GraphHeat和ChebNet这2种图卷积网络(graph convolution net,GCN)分别提取特征信号的低频和高频部分,并获取形变特征的空间关联性,ConvGRUs网络用于提取特征在时间上的关联性,通过三阶段融合方法保留挖掘的信息。为了解决实验数据在时间维度上不充足的问题,引入双层滑动窗口机制。此外,所提模型与其他模型或算法在不同数据集上实验比较,衡量一天和两天预测值的误差指标优于其他模型,而且对大部分节点预测的误差较低。说明模型受样本节点数影响较小,能较好地预测一天和两天的形变,模型学习特征与时空模式的能力较强,泛化性较好。 展开更多
关键词 隧道形变 预测模型 融合时空数据 滑动窗口 图卷积网络(GCN)
下载PDF
A novel configuration model for random graphs with given degree sequence 被引量:1
17
作者 徐新平 刘峰 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期282-286,共5页
Recently, random graphs in which vertices are characterized by hidden variables controlling the establishment of edges between pairs of vertices have attracted much attention. This paper presents a specific realizatio... Recently, random graphs in which vertices are characterized by hidden variables controlling the establishment of edges between pairs of vertices have attracted much attention. This paper presents a specific realization of a class of random network models in which the connection probability between two vertices (i, j) is a specific function of degrees ki and kj. In the framework of the configuration model of random graphsp we find the analytical expressions for the degree correlation and clustering as a function of the variance of the desired degree distribution. The obtained expressions are checked by means of numerical simulations. Possible applications of our model are discussed. 展开更多
关键词 random graphs configuration model CORRELATIONS
下载PDF
A reliability evaluation method for embryonic cellular array based on Markov status graph model 被引量:1
18
作者 WANG Tao CAI Jinyan +1 位作者 MENG Yafeng ZHU Sai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第2期432-446,共15页
Due to the limitations of the existing fault detection methods in the embryonic cellular array(ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, emb... Due to the limitations of the existing fault detection methods in the embryonic cellular array(ECA), the fault detection coverage cannot reach 100%. In order to evaluate the reliability of the ECA more accurately, embryonic cell and its input and output(I/O) resources are considered as a whole, named functional unit(FU). The FU fault detection coverage parameter is introduced to ECA reliability analysis, and a new ECA reliability evaluation method based on the Markov status graph model is proposed.Simulation experiment results indicate that the proposed ECA reliability evaluation method can evaluate the ECA reliability more effectively and accurately. Based on the proposed reliability evaluation method, the influence of parameters change on the ECA reliability is studied, and simulation experiment results show that ECA reliability can be improved by increasing the FU fault detection coverage and reducing the FU failure rate. In addition, by increasing the scale of the ECA, the reliability increases to the maximum first, and then it will decrease continuously. ECA reliability variation rules can not only provide theoretical guidance for the ECA optimization design, but also point out the direction for further research. 展开更多
关键词 EMBRYONIC MARKOV STATUS graph model RELIABILITY FAULT detection evaluation
下载PDF
Thermal-hydraulic modeling and analysis of hydraulic system by pseudo-bond graph 被引量:2
19
作者 胡均平 李科军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2578-2585,共8页
To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they ... To increase the efficiency and reliability of the thermodynamics analysis of the hydraulic system, the method based on pseudo-bond graph is introduced. According to the working mechanism of hydraulic components, they can be separated into two categories: capacitive components and resistive components. Then, the thermal-hydraulic pseudo-bond graphs of capacitive C element and resistance R element were developed, based on the conservation of mass and energy. Subsequently, the connection rule for the pseudo-bond graph elements and the method to construct the complete thermal-hydraulic system model were proposed. On the basis of heat transfer analysis of a typical hydraulic circuit containing a piston pump, the lumped parameter mathematical model of the system was given. The good agreement between the simulation results and experimental data demonstrates the validity of the modeling method. 展开更多
关键词 thermodynamics hydraulic system pseudo-bond graph piston pump modeling temperature simulation
下载PDF
Parallelized User Clicks Recognition from Massive HTTP Data Based on Dependency Graph Model 被引量:1
20
作者 FANG Chcng LIU Jun LEI Zhenming 《China Communications》 SCIE CSCD 2014年第12期13-25,共13页
With increasingly complex website structure and continuously advancing web technologies,accurate user clicks recognition from massive HTTP data,which is critical for web usage mining,becomes more difficult.In this pap... With increasingly complex website structure and continuously advancing web technologies,accurate user clicks recognition from massive HTTP data,which is critical for web usage mining,becomes more difficult.In this paper,we propose a dependency graph model to describe the relationships between web requests.Based on this model,we design and implement a heuristic parallel algorithm to distinguish user clicks with the assistance of cloud computing technology.We evaluate the proposed algorithm with real massive data.The size of the dataset collected from a mobile core network is 228.7GB.It covers more than three million users.The experiment results demonstrate that the proposed algorithm can achieve higher accuracy than previous methods. 展开更多
关键词 cloud computing massive data graph model web usage mining
下载PDF
上一页 1 2 168 下一页 到第
使用帮助 返回顶部