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Graph neural network-based scheduling for multi-UAV-enabled communications in D2D networks
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作者 Pei Li Lingyi Wang +3 位作者 Wei Wu Fuhui Zhou Baoyun Wang Qihui Wu 《Digital Communications and Networks》 SCIE CSCD 2024年第1期45-52,共8页
In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission... In this paper,we jointly design the power control and position dispatch for Multi-Unmanned Aerial Vehicle(UAV)-enabled communication in Device-to-Device(D2D)networks.Our objective is to maximize the total transmission rate of Downlink Users(DUs).Meanwhile,the Quality of Service(QoS)of all D2D users must be satisfied.We comprehensively considered the interference among D2D communications and downlink transmissions.The original problem is strongly non-convex,which requires high computational complexity for traditional optimization methods.And to make matters worse,the results are not necessarily globally optimal.In this paper,we propose a novel Graph Neural Networks(GNN)based approach that can map the considered system into a specific graph structure and achieve the optimal solution in a low complexity manner.Particularly,we first construct a GNN-based model for the proposed network,in which the transmission links and interference links are formulated as vertexes and edges,respectively.Then,by taking the channel state information and the coordinates of ground users as the inputs,as well as the location of UAVs and the transmission power of all transmitters as outputs,we obtain the mapping from inputs to outputs through training the parameters of GNN.Simulation results verified that the way to maximize the total transmission rate of DUs can be extracted effectively via the training on samples.Moreover,it also shows that the performance of proposed GNN-based method is better than that of traditional means. 展开更多
关键词 Unmanned aerial vehicle D2 Dcommunication Graph neural network Power control position planning
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Explosive synchronization in a mobile network in the presence of a positive feedback mechanism
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作者 钱冬杰 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期187-191,共5页
Synchronization is a process that describes the coherent dynamics of a large ensemble of interacting units.The study of explosive synchronization transition attracts considerable attention.Here,I report the explosive ... Synchronization is a process that describes the coherent dynamics of a large ensemble of interacting units.The study of explosive synchronization transition attracts considerable attention.Here,I report the explosive transition within the framework of a mobile network,while each oscillator is controlled by global-order parameters of the system.Using numerical simulation,I find that the explosive synchronization(ES)transition behavior can be controlled by simply adjusting the fraction of controlled oscillators.The influences of some parameters on explosive synchronization are studied.Moreover,due to the presence of the positive feedback mechanism,I prevent the occurrence of the synchronization of continuous-phase transition and make phase transition of the system a first-order phase transition accompanied by a hysteresis loop. 展开更多
关键词 complex network explosive synchronization positive feedback mobile agent
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The realization of positive definite matrices via planar networks and mixing-type sub-cluster algebras
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作者 Diana Ahmad YANG Yi-chao 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2020年第2期127-140,共14页
As an improvement of the combinatorial realization of totally positive matrices via the essential positive weightings of certain planar network by S.Fomin and A.Zelevinsky[7],in this paper,we give a test method of pos... As an improvement of the combinatorial realization of totally positive matrices via the essential positive weightings of certain planar network by S.Fomin and A.Zelevinsky[7],in this paper,we give a test method of positive definite matrices via the planar networks and the so-called mixing-type sub-cluster algebras respectively,introduced here originally.This work firstly gives a combinatorial realization of all matrices through planar network,and then sets up a test method for positive definite matrices by LDU-decompositions and the horizontal weightings of all lines in their planar networks.On the other hand,mainly the relationship is built between positive definite matrices and mixing-type sub-cluster algebras. 展开更多
关键词 positive de nite matrix generalized Jacobi matrix planar network double wiring diagram cluster subalgebras
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“阴/阳”和“positive/negative”之多义现象的认知对比研究
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作者 刘臻 张珊珊 梅德明 《语言教育》 2014年第4期53-56,60,共5页
多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点,已取得了不少的研究成果,但是对于"阴/阳"和"positive/negative"这两组具有独特民族特色的字词的语... 多义现象是当今语言学研究的一个重要方面,从认知语言学的视角对多义现象进行对比研究是当今语义研究的一个热点,已取得了不少的研究成果,但是对于"阴/阳"和"positive/negative"这两组具有独特民族特色的字词的语义研究尚鲜有关注。本文从原型范畴和认知隐喻的视角,详细地分析了这两组字词的语义发展特征,发现它们的语义已经形成错综复杂的语义网状结构,既有语义重合之处,也有自己的独特之处,体现了中西文化的独特文化特征和思维特征。 展开更多
关键词 阴/阳 positive/negative 认知 多义现象 语义网络
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Portable Dynamic Positioning Control System on A Barge in Short-Crested Waves Using the Neural Network Algorithm 被引量:2
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作者 FANG Ming-chung LEE Zi-yi 《China Ocean Engineering》 SCIE EI CSCD 2013年第4期469-480,共12页
This paper develops a nonlinear mathematical model to simulate the dynamic motion behavior of the barge equipped with the portable outboard Dynamic Positioning (DP) system in short-crested waves. The self-tuning Pro... This paper develops a nonlinear mathematical model to simulate the dynamic motion behavior of the barge equipped with the portable outboard Dynamic Positioning (DP) system in short-crested waves. The self-tuning Proportional- Derivative (PD) controller based on the neural network algorithm is applied to control the thrusters for optimal adjustment of the barge position in waves. In addition to the wave, the current, the wind and the nonlinear drift force are also considered in the calculations. The time domain simulations for the six-degree-of-freedom motions of the barge with the DP system are solved by the 4th order Runge-Kutta method which can compromise the efficiency and the accuracy of the simulations. The technique of the portable alternative DP system developed here can serve as a practical tool to assist those ships without being equipped with the DP facility while the dynamic positioning missions are needed. 展开更多
关键词 neural network PD controller dynamic positioning short-crested wave
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Decentralized adaptive neural network sliding mode position/force control of constrained reconfigurable manipulators 被引量:2
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作者 李元春 丁贵彬 赵博 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2917-2925,共9页
A decentralized adaptive neural network sliding mode position/force control scheme is proposed for constrained reconfigurable manipulators. Different from the decentralized control strategy in multi-manipulator cooper... A decentralized adaptive neural network sliding mode position/force control scheme is proposed for constrained reconfigurable manipulators. Different from the decentralized control strategy in multi-manipulator cooperation, the proposed decentralized position/force control scheme can be applied to series constrained reconfigurable manipulators. By multiplying each row of Jacobian matrix in the dynamics by contact force vector, the converted joint torque is obtained. Furthermore, using desired information of other joints instead of their actual values, the dynamics can be represented as a set of interconnected subsystems by model decomposition technique. An adaptive neural network controller is introduced to approximate the unknown dynamics of subsystem. The interconnection and the whole error term are removed by employing an adaptive sliding mode term. And then, the Lyapunov stability theory guarantees the stability of the closed-loop system. Finally, two reconfigurable manipulators with different configurations are employed to show the effectiveness of the proposed decentralized position/force control scheme. 展开更多
关键词 constrained reconfigurable manipulators position/force control model decomposition decentralized control neural network
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Position Encoding Based Convolutional Neural Networks for Machine Remaining Useful Life Prediction 被引量:2
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作者 Ruibing Jin Min Wu +3 位作者 Keyu Wu Kaizhou Gao Zhenghua Chen Xiaoli Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第8期1427-1439,共13页
Accurate remaining useful life(RUL)prediction is important in industrial systems.It prevents machines from working under failure conditions,and ensures that the industrial system works reliably and efficiently.Recentl... Accurate remaining useful life(RUL)prediction is important in industrial systems.It prevents machines from working under failure conditions,and ensures that the industrial system works reliably and efficiently.Recently,many deep learning based methods have been proposed to predict RUL.Among these methods,recurrent neural network(RNN)based approaches show a strong capability of capturing sequential information.This allows RNN based methods to perform better than convolutional neural network(CNN)based approaches on the RUL prediction task.In this paper,we question this common paradigm and argue that existing CNN based approaches are not designed according to the classic principles of CNN,which reduces their performances.Additionally,the capacity of capturing sequential information is highly affected by the receptive field of CNN,which is neglected by existing CNN based methods.To solve these problems,we propose a series of new CNNs,which show competitive results to RNN based methods.Compared with RNN,CNN processes the input signals in parallel so that the temporal sequence is not easily determined.To alleviate this issue,a position encoding scheme is developed to enhance the sequential information encoded by a CNN.Hence,our proposed position encoding based CNN called PE-Net is further improved and even performs better than RNN based methods.Extensive experiments are conducted on the C-MAPSS dataset,where our PE-Net shows state-of-the-art performance. 展开更多
关键词 Convolutional neural network(CNN) deep learning position encoding remaining useful life prediction
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Printed Surface Defect Detection Model Based on Positive Samples 被引量:1
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作者 Xin Zihao Wang Hongyuan +3 位作者 Qi Pengyu Du Weidong Zhang Ji Chen Fuhua 《Computers, Materials & Continua》 SCIE EI 2022年第9期5925-5938,共14页
For a long time, the detection and extraction of printed surfacedefects has been a hot issue in the print industry. Nowadays, defect detectionof a large number of products still relies on traditional image processinga... For a long time, the detection and extraction of printed surfacedefects has been a hot issue in the print industry. Nowadays, defect detectionof a large number of products still relies on traditional image processingalgorithms such as scale invariant feature transform (SIFT) and orientedfast and rotated brief (ORB), and researchers need to design algorithms forspecific products. At present, a large number of defect detection algorithmsbased on object detection have been applied but need lots of labeling sampleswith defects. Besides, there are many kinds of defects in printed surface,so it is difficult to enumerate all defects. Most defect detection based onunsupervised learning of positive samples use generative adversarial networks(GAN) and variational auto-encoders (VAE) algorithms, but these methodsare not effective for complex printed surface. Aiming at these problems, Inthis paper, an unsupervised defect detection and extraction algorithm forprinted surface based on positive samples in the complex printed surface isproposed innovatively. We propose a kind of defect detection and extractionnetwork based on image matching network. This network is divided into thefull convolution network of feature points extraction, and the graph attentionnetwork using self attention and cross attention. Though the key pointsextraction network, we can get robustness key points in the complex printedimages, and the graph network can solve the problem of the deviation becauseof different camera positions and the influence of defect in the differentproduction lines. Just one positive sample image is needed as the benchmarkto detect the defects. The algorithm in this paper has been proved in “TheFirst ZhengTu Cup on Campus Machine Vision AI Competition” and gotexcellent results in the finals. We are working with the company to apply it inproduction. 展开更多
关键词 Unsupervised learning printed surface defect extraction full convolution network graph attention network positive sample
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Residual Network with Enhanced Positional Attention and Global Prior for Clothing Parsing 被引量:1
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作者 王绍宇 胡芸 +3 位作者 朱艾安 叶少萍 秦彦霞 石秀金 《Journal of Donghua University(English Edition)》 CAS 2022年第5期505-510,共6页
Clothing parsing, also known as clothing image segmentation, is the problem of assigning a clothing category label to each pixel in clothing images. To address the lack of positional and global prior in existing cloth... Clothing parsing, also known as clothing image segmentation, is the problem of assigning a clothing category label to each pixel in clothing images. To address the lack of positional and global prior in existing clothing parsing algorithms, this paper proposes an enhanced positional attention module(EPAM) to collect positional information in the vertical direction of each pixel, and an efficient global prior module(GPM) to aggregate contextual information from different sub-regions. The EPAM and GPM based residual network(EG-ResNet) could effectively exploit the intrinsic features of clothing images while capturing information between different scales and sub-regions. Experimental results show that the proposed EG-ResNet achieves promising performance in clothing parsing of the colorful fashion parsing dataset(CFPD)(51.12% of mean Intersection over Union(mIoU) and 92.79% of pixel-wise accuracy(PA)) compared with other state-of-the-art methods. 展开更多
关键词 clothing parsing convolutional neural network positional attention global prior
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New Distributed Positioning Algorithm Based on Centroid of Circular Belt for Wireless Sensor Networks
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作者 Xu-Zhi Lai Simon X. Yang +2 位作者 Gui-Xiu Zeng Jin-Hua She Min Wu 《International Journal of Automation and computing》 EI 2007年第3期315-324,共10页
This paper presents a new distributed positioning algorithm for unknown nodes in a wireless sensor network. The algorithm is based exclusively on connectivity. First, assuming that the positions of the anchor nodes ar... This paper presents a new distributed positioning algorithm for unknown nodes in a wireless sensor network. The algorithm is based exclusively on connectivity. First, assuming that the positions of the anchor nodes are already known, a circular belt containing an unknown node is obtained using information about the anchor nodes that are in radio range of the unknown node, based on the geometric relationships and communication constraints among the unknown node and the anchor nodes. Then, the centroid of the circular belt is taken to be the estimated position of the unknown node. Since the algorithm is very simple and since the only communication needed is between the anchor nodes and the unknown node, the communication and computational loads are very small. Furthermore, the algorithm is robust because neither the failure of old unknown nodes nor the addition of new unknown nodes influences the positioning of unknown nodes to be located. A theoretical analysis and simulation results show that the algorithm does not produce any cumulative error and is insensitive to range error, and that a change in the number of sensor nodes does not affect the communication or computational load. These features make this algorithm suitable for all sizes of low-power wireless sensor networks. 展开更多
关键词 positIONING wireless sensor networks circular belt algorithm performance.
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An artificial neural network for detecting weld position in arc welding process
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作者 高向东 黄石生 余英林 《China Welding》 EI CAS 1999年第1期76-82,共7页
A kind of self organizing artificial neural network used for weld detection is presented in this paper, and its concepts and issues are discussed. The network can transform the weld visual information into typical pa... A kind of self organizing artificial neural network used for weld detection is presented in this paper, and its concepts and issues are discussed. The network can transform the weld visual information into typical patterns and match with the weld data collected on line, and so realize the accurate detection of the weld position in arc welding process. 展开更多
关键词 artificial neural networks self adaptive resonance theory VISION weld position detection
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Application of Artificial Neural Network in Robotic Hybrid Position/Force Control
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作者 陈卫东 《High Technology Letters》 EI CAS 1996年第1期26-29,共4页
A hybrid position/force controller is designed for the joint 2 and the joint 3 of thePUMA 560 robot.The hybrid controller includes a multilayered neural network,which canidentify the dynamics of the contacted environm... A hybrid position/force controller is designed for the joint 2 and the joint 3 of thePUMA 560 robot.The hybrid controller includes a multilayered neural network,which canidentify the dynamics of the contacted environment and can optimize the parameters of PIDcontroller.The experimental results show that after having been trained,the robot has sta-ble response to the training patterns and strong adaptive ability to the situation between thepatterns. 展开更多
关键词 ROBOTIC hybrid position/force CONTROL Adaptive PID CONTROL FEEDFORWARD network BP algorithm Training pattern
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Vehicle Positioning Method Based on RFID in Vehicular Ad-Hoc Networks
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作者 于德新 郑坤 张伟 《Journal of Donghua University(English Edition)》 EI CAS 2015年第5期800-806,共7页
With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accurac... With the rapid development of vehicular ad hoc network( VANET) technology,VANET applications such as safe driving and emergency rescue demand high position accuracy,but traditional GPS is difficult to meet new accuracy requirements. To overcome this limitation,a new vehicle positioning method based on radio frequency identification( RFID) is proposed. First RFID base stations are divided into three categories using fuzzy technology,and then Chan algorithm is used to calculate three vehicles' positions,which are weighed to acquire vehicles' accurate position. This method can effectively overcome the problem that vehicle positioning accuracy is not high resulting from the factors such as ambient noise and base distribution when Chan algorithm is used. Experimental results show that the performance of the proposed method is superior to Chan algorithm and 2-step algorithm based on averaging method,which can satisfy the requirements of vehicle positioning in VANETs. 展开更多
关键词 vehicular ad-hoc network(VANET) radio frequency identification(RFID) vehicle positioning fuzzy technology
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Positioning a Node of Wireless Sensor Networks in 3 Dimensional Space
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作者 Wenhui NIE Shiguang JU +1 位作者 Anrong XUE Feng LI 《International Journal of Communications, Network and System Sciences》 2009年第6期540-545,共6页
To know the location of nodes is very important and valuable for wireless sensor networks (WSN), we present an improved positioning model (3D-PMWSN) to locate the nodes in WSN. In this model, grid in space is presente... To know the location of nodes is very important and valuable for wireless sensor networks (WSN), we present an improved positioning model (3D-PMWSN) to locate the nodes in WSN. In this model, grid in space is presented. When one tag is detected by a certain reader whose position is known, the tag’s position can be known through certain algorithm. The error estimation is given. Emulation shows that the positioning speed is relatively fast and positioning precision is relatively high. 展开更多
关键词 WIRELESS Sensor network Cells READER TAG positIONING
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Mobile Positioning System Based on the Wireless Sensor Network in Buildings
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作者 Xiujun LI Gang SUN Xu WANG 《Communications and Network》 2009年第2期96-100,共5页
Established on the Intel Multi-Core Embedded platform, using 802.11 Wireless Network protocols as the communication medium, combining with Radio Frequency-Communication and Ultrasonic Ranging, imple-ment a mobile term... Established on the Intel Multi-Core Embedded platform, using 802.11 Wireless Network protocols as the communication medium, combining with Radio Frequency-Communication and Ultrasonic Ranging, imple-ment a mobile terminal system in an intellectualized building. It can provide its holder such functions: 1) Accurate Positioning 2) Intelligent Navigation 3) Video Monitoring 4) Wireless Communication. The inno-vative point for this paper is to apply the multi-core computing on the embedded system to promote its com-puting speed and give a real-time performance and apply this system into the indoor environment for the purpose of emergent event or rescuing. 展开更多
关键词 positIONING Intelligent NAVIGATION VIDEO Transmission Wireless Communication Sensor networks MULTI-CORE COMPUTING
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Application of the Spectrum Peak Positioning Technology Based on BP Neural Network in Demodulation of Cavity Length of EFPI Fiber Optical Sensor
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作者 Mengran Zhou Mengya Nie 《Journal of Computer and Communications》 2013年第7期67-71,共5页
An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the ca... An Extrinsic Fabry-Perot Interferometric (EFPI) fiber optical sensor system is an online testing system for the gas density. The system achieves the measurement of gas density information mainly by demodulating the cavity length of EF- PI fiber optical sensor. There are many ways to achieve the demodulation of the cavity length. For shortcomings of the big intensity demodulation error and complex structure of phase demodulation, this paper proposes that BP neural net-work is used to locate the special peak points in normalized interference spectrum and combining the advantages of the unimodal and bimodal measurement achieves the demodulation of the cavity length. Through online simulation and actual measurement, the results show that the peak positioning technology based on BP neural network can not only achieve high-precision demodulation of the cavity length, but also achieve an absolute measurement of cavity length in large dynamic range. 展开更多
关键词 EFPI Fiber Optical Sensor The DEMODULATION of CAVITY Length BP NEURAL network The PEAK positIONING Technology
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Changes of China's Position in the World Food Trade Network
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作者 Congxian HE Xiuxiang LI 《Asian Agricultural Research》 2021年第8期9-13,共5页
"Ensuring stability in foreign trade"and"ensuring food security"are essential parts of China's"six priorities"and"stability in six areas".Based on the data of bilateral food... "Ensuring stability in foreign trade"and"ensuring food security"are essential parts of China's"six priorities"and"stability in six areas".Based on the data of bilateral food trade between countries during 1996-2018,using descriptive statistical analysis and social network analysis methods,this paper analyzed the changes of China's trade position in the world food trade network.It reached the following results.(i)China's position in the trade network has undergone a phased process of"remarkable improvement-continuous fluctuation-significant decline-steady growth".(ii)Export participation is better than import participation,the gap between trade export strength and import strength is widening,and the effective scale and constraint index gradually improve.(iii)The change of China's position in the food trade network is affected by geographical,economic,institutional and cultural factors.In view of these findings,it is recommended to improve node centrality,enhance network participation,improve network interconnection,and prevent international market risks,so as to better deal with the complex international environment. 展开更多
关键词 Food security Food trade network Social network analysis China's position
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Deep convolutional adversarial graph autoencoder using positive pointwise mutual information for graph embedding
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作者 马秀慧 WANG Rong +3 位作者 CHEN Shudong DU Rong ZHU Danyang ZHAO Hua 《High Technology Letters》 EI CAS 2022年第1期98-106,共9页
Graph embedding aims to map the high-dimensional nodes to a low-dimensional space and learns the graph relationship from its latent representations.Most existing graph embedding methods focus on the topological struct... Graph embedding aims to map the high-dimensional nodes to a low-dimensional space and learns the graph relationship from its latent representations.Most existing graph embedding methods focus on the topological structure of graph data,but ignore the semantic information of graph data,which results in the unsatisfied performance in practical applications.To overcome the problem,this paper proposes a novel deep convolutional adversarial graph autoencoder(GAE)model.To embed the semantic information between nodes in the graph data,the random walk strategy is first used to construct the positive pointwise mutual information(PPMI)matrix,then,graph convolutional net-work(GCN)is employed to encode the PPMI matrix and node content into the latent representation.Finally,the learned latent representation is used to reconstruct the topological structure of the graph data by decoder.Furthermore,the deep convolutional adversarial training algorithm is introduced to make the learned latent representation conform to the prior distribution better.The state-of-the-art experimental results on the graph data validate the effectiveness of the proposed model in the link prediction,node clustering and graph visualization tasks for three standard datasets,Cora,Citeseer and Pubmed. 展开更多
关键词 graph autoencoder(GAE) positive pointwise mutual information(PPMI) deep convolutional generative adversarial network(DCGAN) graph convolutional network(GCN) se-mantic information
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ZTE Strengthens West African Mobile Market Position with National GSM Network and Introduction of GPRS Services
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《ZTE Communications》 2005年第1期61-61,共1页
关键词 ZTE Strengthens West African Mobile Market position with National GSM network and Introduction of GPRS Services GSM GPRS WEST
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GPS Rapid Static and Kinematic Positioning Based on GPS Active Network
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作者 CHEN Wu HU Congwei CHEN Yongqi DING Xiaoli Simon Chi_wo Kowk 《Geo-Spatial Information Science》 2003年第1期5-11,共7页
This paper presents a data processing strategy for GPS kinematic positioning by using a GPS active network to model the GPS errors in double difference observable.Firstly,the double difference residuals are estimated ... This paper presents a data processing strategy for GPS kinematic positioning by using a GPS active network to model the GPS errors in double difference observable.Firstly,the double difference residuals are estimated between the reference stations in the active network.Then the errors at a user station are predicted as the network corrections to user measurements,based on the location of the user.Finally conventional kinematic positioning algorithms can be applied to determine the position of the user station.As an example,continuous 24_hour GPS data in March 2001 has been processed by this method.It clearly demonstrates that,after applying these corrections to a user within the network,both the success rate for ambiguity resolution and the positioning accuracy have been significantly improved. 展开更多
关键词 全球定位系统 GPS 运动学 活动网络 测量误差 模糊度
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