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A Graph with Adaptive AdjacencyMatrix for Relation Extraction
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作者 Run Yang YanpingChen +1 位作者 Jiaxin Yan Yongbin Qin 《Computers, Materials & Continua》 SCIE EI 2024年第9期4129-4147,共19页
The relation is a semantic expression relevant to two named entities in a sentence.Since a sentence usually contains several named entities,it is essential to learn a structured sentence representation that encodes de... The relation is a semantic expression relevant to two named entities in a sentence.Since a sentence usually contains several named entities,it is essential to learn a structured sentence representation that encodes dependency information specific to the two named entities.In related work,graph convolutional neural networks are widely adopted to learn semantic dependencies,where a dependency tree initializes the adjacency matrix.However,this approach has two main issues.First,parsing a sentence heavily relies on external toolkits,which can be errorprone.Second,the dependency tree only encodes the syntactical structure of a sentence,which may not align with the relational semantic expression.In this paper,we propose an automatic graph learningmethod to autonomously learn a sentence’s structural information.Instead of using a fixed adjacency matrix initialized by a dependency tree,we introduce an Adaptive Adjacency Matrix to encode the semantic dependency between tokens.The elements of thismatrix are dynamically learned during the training process and optimized by task-relevant learning objectives,enabling the construction of task-relevant semantic dependencies within a sentence.Our model demonstrates superior performance on the TACRED and SemEval 2010 datasets,surpassing previous works by 1.3%and 0.8%,respectively.These experimental results show that our model excels in the relation extraction task,outperforming prior models. 展开更多
关键词 Relation extraction graph convolutional neural network adaptive adjacency matrix
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AFSTGCN:Prediction for multivariate time series using an adaptive fused spatial-temporal graph convolutional network
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作者 Yuteng Xiao Kaijian Xia +5 位作者 Hongsheng Yin Yu-Dong Zhang Zhenjiang Qian Zhaoyang Liu Yuehan Liang Xiaodan Li 《Digital Communications and Networks》 SCIE CSCD 2024年第2期292-303,共12页
The prediction for Multivariate Time Series(MTS)explores the interrelationships among variables at historical moments,extracts their relevant characteristics,and is widely used in finance,weather,complex industries an... The prediction for Multivariate Time Series(MTS)explores the interrelationships among variables at historical moments,extracts their relevant characteristics,and is widely used in finance,weather,complex industries and other fields.Furthermore,it is important to construct a digital twin system.However,existing methods do not take full advantage of the potential properties of variables,which results in poor predicted accuracy.In this paper,we propose the Adaptive Fused Spatial-Temporal Graph Convolutional Network(AFSTGCN).First,to address the problem of the unknown spatial-temporal structure,we construct the Adaptive Fused Spatial-Temporal Graph(AFSTG)layer.Specifically,we fuse the spatial-temporal graph based on the interrelationship of spatial graphs.Simultaneously,we construct the adaptive adjacency matrix of the spatial-temporal graph using node embedding methods.Subsequently,to overcome the insufficient extraction of disordered correlation features,we construct the Adaptive Fused Spatial-Temporal Graph Convolutional(AFSTGC)module.The module forces the reordering of disordered temporal,spatial and spatial-temporal dependencies into rule-like data.AFSTGCN dynamically and synchronously acquires potential temporal,spatial and spatial-temporal correlations,thereby fully extracting rich hierarchical feature information to enhance the predicted accuracy.Experiments on different types of MTS datasets demonstrate that the model achieves state-of-the-art single-step and multi-step performance compared with eight other deep learning models. 展开更多
关键词 adaptive adjacency matrix Digital twin Graph convolutional network Multivariate time series prediction Spatial-temporal graph
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A Binary Images Watermarking Algorithm Based on Adaptable Matrix 被引量:1
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作者 ZHANG Fan ZHANG Junliang 《Wuhan University Journal of Natural Sciences》 CAS 2008年第5期595-599,共5页
A watermarking algorithm of binary images using adaptable matrix is presented. An adaptable matrix is designed to evaluate the smoothness and the connectivity of binary images. The watermark is embedded according to t... A watermarking algorithm of binary images using adaptable matrix is presented. An adaptable matrix is designed to evaluate the smoothness and the connectivity of binary images. The watermark is embedded according to the adaptable matrix in this algorithm. In the proposed watermarking algorithm, each image block implements a XOR operation with the binary adaptable matrix, which has the same size with the image block, and in order to embed the watermark data, a multiplication operation are also implemented with the weight matrix. The experimental results show that proposed scheme has a good performance. 展开更多
关键词 WATERMARKING binary image adaptable matrix
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Countermeasures of adaptation to climate change:establishment and application for implementation matrix 被引量:1
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作者 Jiang Dongmei Liu Bin 《Ecological Economy》 2009年第2期102-111,共10页
In the conceptual framework of adaptation policy assessment to climate change, adaptation measures can be categorized as two groups:facilitation and implementation. Facilitation measures refers to activities that enh... In the conceptual framework of adaptation policy assessment to climate change, adaptation measures can be categorized as two groups:facilitation and implementation. Facilitation measures refers to activities that enhance adaptive capacity, while implementation refers to activities that actually avoid adverse climate impacts on a system by reducing its exposure or sensitivity to climatic hazards, or by moderating relevant non-climatic factors. This paper aims to establish a matrix of implementation measures of adaptation to climate change, through four different ways how adaptation can influencc the relevant elements of climate change. reducing the exposure, reducing the sensitivity, alleviating the adverse impacts and reducing the negative non-climatic factors, and then further discuss the particular implementation measures of adaptation to climate change, through application studies on the selected sub-systems, intend to organize the disordered implementation measures in existent, and put forward some new measures under the guidance of this matrix, which could enrich and promote the system and content of implementation measures of adaptation. 展开更多
关键词 Adaptation to climate change hnplementation of adaptation matrix of implementation
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A KIND OF URN MODEL FOR ADAPTIVE SEQUENTIAL DESIGN
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作者 白志东 陈桂景 胡飞芳 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期224-228,共5页
This paper proposes a new kind of generalized Friendman's urn model,which with adaptive nonhomogeneous generating matrix.This model may be applied in sequential medical experiment.In this model some limit theorems... This paper proposes a new kind of generalized Friendman's urn model,which with adaptive nonhomogeneous generating matrix.This model may be applied in sequential medical experiment.In this model some limit theorems (strong consistency and asymptot- ical normality) have been obtained. 展开更多
关键词 Generalized Friedman's urn adaptive sequetial design generating matrix strong consistency asymptotical normality
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Secured Cloud Data Migration Technique by Competent Probabilistic Public Key Encryption 被引量:3
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作者 M.G.Aruna K.G.Mohan 《China Communications》 SCIE CSCD 2020年第5期168-190,共23页
Cloud computing, a recently emerged paradigm faces major challenges in achieving the privacy of migrated data, network security, etc. Too many cryptographic technologies are raised to solve these issues based on ident... Cloud computing, a recently emerged paradigm faces major challenges in achieving the privacy of migrated data, network security, etc. Too many cryptographic technologies are raised to solve these issues based on identity, attributes and prediction algorithms yet;these techniques are highly prone to attackers. This would raise a need of an effective encryption technique, which would ensure secure data migration. With this scenario, our proposed methodology Efficient Probabilistic Public Key Encryption(EPPKE) is optimized with Covariance Matrix Adaptation Evolution Strategies(CMA-ES). It ensures data integrity through the Luhn algorithm with BLAKE 2b encapsulation. This enables an optimized security to the data which is migrated through cloud. The proposed methodology is implemented in Open Stack with Java Language. It achieves better results by providing security compared to other existing techniques like RSA, IBA, ABE, PBE, etc. 展开更多
关键词 Luhn algorithm ENCRYPTION efficient probabilistic public key encryption(EPPKE) covariance matrix adaptation evolution strategies(CMA-ES) trusted third party(TTP)
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A New Model for Network Security Situation Assessment of the Industrial Internet 被引量:1
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作者 Ming Cheng Shiming Li +3 位作者 Yuhe Wang Guohui Zhou Peng Han Yan Zhao 《Computers, Materials & Continua》 SCIE EI 2023年第5期2527-2555,共29页
To address the problem of network security situation assessment in the Industrial Internet,this paper adopts the evidential reasoning(ER)algorithm and belief rule base(BRB)method to establish an assessment model.First... To address the problem of network security situation assessment in the Industrial Internet,this paper adopts the evidential reasoning(ER)algorithm and belief rule base(BRB)method to establish an assessment model.First,this paper analyzes the influencing factors of the Industrial Internet and selects evaluation indicators that contain not only quantitative data but also qualitative knowledge.Second,the evaluation indicators are fused with expert knowledge and the ER algorithm.According to the fusion results,a network security situation assessment model of the Industrial Internet based on the ER and BRB method is established,and the projection covariance matrix adaptive evolution strategy(P-CMA-ES)is used to optimize the model parameters.This method can not only utilize semiquantitative information effectively but also use more uncertain information and prevent the problem of combinatorial explosion.Moreover,it solves the problem of the uncertainty of expert knowledge and overcomes the problem of low modeling accuracy caused by insufficient data.Finally,a network security situation assessment case of the Industrial Internet is analyzed to verify the effectiveness and superiority of the method.The research results showthat this method has strong applicability to the network security situation assessment of complex Industrial Internet systems.It can accurately reflect the actual network security situation of Industrial Internet systems and provide safe and reliable suggestions for network administrators to take timely countermeasures,thereby improving the risk monitoring and emergency response capabilities of the Industrial Internet. 展开更多
关键词 Industrial internet network security situation assessment evidential reasoning belief rule base projection covariance matrix adaptive evolution strategy
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Frequency-invariant robust adaptive beamforming based on interference covariance matrix reconstruction 被引量:6
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作者 FAN Zhan LIANG Guolong 《Chinese Journal of Acoustics》 2014年第4期359-368,共10页
Consider the problems of frequency-invariant beampattern optimization and robustness in broadband beamforming.Firstly,a global optimization algorithm,which is based on phase compensation of the array manifolds,is used... Consider the problems of frequency-invariant beampattern optimization and robustness in broadband beamforming.Firstly,a global optimization algorithm,which is based on phase compensation of the array manifolds,is used to construct the frequency-invariant beampattern.Compared with some methods presented recently,the proposed algorithm is not only available to get the global optimal solution,but also simple for physical realization.Meanwhile,a robust adaptive broadband beamforming algorithm is also derived by reconstructing the covariance matrix.The essence of the proposed algorithm is to estimate the space-frequency spectrum using Capon estimator firstly,then integrate over a region separated from the desired signal direction to reconstruct the interference-plus-noise covariance matrix,and finally caleulate the adaptive beamformer weights with the reconstructed matrix.The design of beamformer is formulated as a convex optimization problem to be solved.Simulation results show that the performance of the proposed algorithm is almost always close to the optimal value across a wide range of signal to noise ratios. 展开更多
关键词 Frequency-invariant robust adaptive beamforming based on interference covariance matrix reconstruction
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Aberration correction for multiphoton microscopy using covariance matrix adaptation evolution strategy 被引量:1
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作者 王科 郑磊 +8 位作者 秦梦圆 张万剑 邓想全 仝申 程慧 黄杰 钟金成 张颖娴 邱娉 《Chinese Optics Letters》 SCIE EI CAS CSCD 2023年第5期88-93,共6页
Multiphoton microscopy is the enabling tool for biomedical research,but the aberrations of biological tissues have limited its imaging performance.Adaptive optics(AO)has been developed to partially overcome aberration... Multiphoton microscopy is the enabling tool for biomedical research,but the aberrations of biological tissues have limited its imaging performance.Adaptive optics(AO)has been developed to partially overcome aberration to restore imaging performance.For indirect AO,algorithm is the key to its successful implementation.Here,based on the fact that indirect AO has an analogy to the black-box optimization problem,we successfully apply the covariance matrix adaptation evolution strategy(CMA-ES)used in the latter,to indirect AO in multiphoton microscopy(MPM).Compared with the traditional genetic algorithm(GA),our algorithm has a greater improvement in convergence speed and convergence accuracy,which provides the possibility of realizing real-time dynamic aberration correction for deep in vivo biological tissues. 展开更多
关键词 multiphoton microscopy 1700-nm window adaptive optics covariance matrix adaptation evolution strategy
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Efficient multi-objective CMA-ES algorithm assisted by knowledge-extraction-based variable-fidelity surrogate model
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作者 Zengcong LI Kuo TIAN +1 位作者 Shu ZHANG Bo WANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第6期213-232,共20页
To accelerate the multi-objective optimization for expensive engineering cases, a Knowledge-Extraction-based Variable-Fidelity Surrogate-assisted Covariance Matrix Adaptation Evolution Strategy(KE-VFS-CMA-ES) is prese... To accelerate the multi-objective optimization for expensive engineering cases, a Knowledge-Extraction-based Variable-Fidelity Surrogate-assisted Covariance Matrix Adaptation Evolution Strategy(KE-VFS-CMA-ES) is presented. In the first part, the KE-VFS model is established. Firstly, the optimization is performed using the low-fidelity surrogate model to obtain the Low-Fidelity Non-Dominated Solutions(LF-NDS). Secondly, aiming to obtain the High-Fidelity(HF) sample points located in promising areas, the K-means clustering algorithm and the space-filling strategy are used to extract knowledge from the LF-NDS to the HF space. Finally,the KE-VFS model is established by means of the obtained HF and LF sample points. In the second part, a novel model management based on the Modified Hypervolume Improvement(MHVI) criterion and pre-screening strategy is proposed. In each generation of KE-VFS-CMA-ES, excessive candidate points are firstly generated and then calculated by the MHVI criterion to find out a few potential points, which will be evaluated by the HF model. Through the above two parts,the promising areas can be detected and the potential points can be screened out, which contributes to speeding up the optimization process twofold. Three classic benchmark functions and a time-consuming engineering case of the aerospace integrally stiffened shell are studied, and results illustrate the excellent efficiency, robustness and applicability of KE-VFS-CMA-ES compared with other four known multi-objective optimization algorithms. 展开更多
关键词 Covariance matrix adaptation evolution strategy Model management Multi-objective optimization Surrogate-assisted evolutionary algorithm Variable-fidelity surrogate model
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Network security situation automatic prediction model based on accumulative CMA-ES optimization
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作者 Wang Jian Li Ke Zhao Guosheng 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2017年第3期33-43,共11页
To improve the accuracy of the network security situation, a security situation automatic prediction model based on accumulative data preprocess and support vector machine (SVM) optimized by covariance matrix adapti... To improve the accuracy of the network security situation, a security situation automatic prediction model based on accumulative data preprocess and support vector machine (SVM) optimized by covariance matrix adaptive evolutionary strategy (CMA-ES) is proposed. The proposed model adopts SVM which has strong nonlinear ability. Also, the hyper parameters for SVM are optimized through the CMA-ES which owns good performance in finding optimization automatically. Considering the irregularity of network security situation values, we accumulate the original sequence, so that the internal rules of discrete data can be revealed and it is easy to model. Simulation experiments show that the proposed model has faster convergence-speed and higher prediction accuracy than other extant prediction models. 展开更多
关键词 security situation automatic prediction covariance matrix adaptive evolution strategy support vector machine
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