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The Immense Impact of Reverse Edges on Large Hierarchical Networks
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作者 Haosen Cao Bin-Bin Hu +7 位作者 Xiaoyu Mo Duxin Chen Jianxi Gao Ye Yuan Guanrong Chen Tamás Vicsek Xiaohong Guan Hai-Tao Zhang 《Engineering》 SCIE EI CAS CSCD 2024年第5期240-249,共10页
Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so forth.The struc... Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so forth.The structure of a large directed hierarchical network is often strongly influenced by reverse edges from lower-to higher-level nodes,such as lagging birds’howl in a flock or the opinions of lowerlevel individuals feeding back to higher-level ones in a social group.This study reveals that,for most large-scale real hierarchical networks,the majority of the reverse edges do not affect the synchronization process of the entire network;the synchronization process is influenced only by a small part of these reverse edges along specific paths.More surprisingly,a single effective reverse edge can slow down the synchronization of a huge hierarchical network by over 60%.The effect of such edges depends not on the network size but only on the average in-degree of the involved subnetwork.The overwhelming majority of active reverse edges turn out to have some kind of“bunching”effect on the information flows of hierarchical networks,which slows down synchronization processes.This finding refines the current understanding of the role of reverse edges in many natural,social,and engineering hierarchical networks,which might be beneficial for precisely tuning the synchronization rhythms of these networks.Our study also proposes an effective way to attack a hierarchical network by adding a malicious reverse edge to it and provides some guidance for protecting a network by screening out the specific small proportion of vulnerable nodes. 展开更多
关键词 SYNCHRONIZABILITY Large hierarchical networks Reverse edges Information flows Complex networks
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Verifying hierarchical network nonlocality in general quantum networks
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作者 杨舒媛 侯晋川 贺衎 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期199-208,共10页
Recently, a class of innovative notions on quantum network nonlocality(QNN), called full quantum network nonlocality(FQNN), have been proposed in Phys. Rev. Lett. 128 010403(2022). As the generalization of full networ... Recently, a class of innovative notions on quantum network nonlocality(QNN), called full quantum network nonlocality(FQNN), have been proposed in Phys. Rev. Lett. 128 010403(2022). As the generalization of full network nonlocality(FNN), l-level quantum network nonlocality(l-QNN) was defined in arxiv. 2306.15717 quant-ph(2024). FQNN is a NN that can be generated only from a network with all sources being non-classical. This is beyond the existing standard network nonlocality, which may be generated from a network with only a non-classical source. One of the challenging tasks is to establish corresponding Bell-like inequalities to demonstrate the FQNN or l-QNN. Up to now, the inequality criteria for FQNN and l-QNN have only been established for star and chain networks. In this paper, we devote ourselves to establishing Bell-like inequalities for networks with more complex structures. Note that star and chain networks are special kinds of tree-shaped networks. We first establish the Bell-like inequalities for verifying l-QNN in k-forked tree-shaped networks. Such results generalize the existing inequalities for star and chain networks. Furthermore, we find the Bell-like inequality criteria for l-QNN for general acyclic and cyclic networks. Finally, we discuss the demonstration of l-QNN in the well-known butterfly networks. 展开更多
关键词 full network nonlocality hierarchical network nonlocality tree network
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Cross-Target Stance Detection with Sentiments-Aware Hierarchical Attention Network
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作者 Kelan Ren Facheng Yan +3 位作者 Honghua Chen Wen Jiang Bin Wei Mingshu Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第10期789-807,共19页
The task of cross-target stance detection faces significant challenges due to the lack of additional background information in emerging knowledge domains and the colloquial nature of language patterns.Traditional stan... The task of cross-target stance detection faces significant challenges due to the lack of additional background information in emerging knowledge domains and the colloquial nature of language patterns.Traditional stance detection methods often struggle with understanding limited context and have insufficient generalization across diverse sentiments and semantic structures.This paper focuses on effectively mining and utilizing sentimentsemantics knowledge for stance knowledge transfer and proposes a sentiment-aware hierarchical attention network(SentiHAN)for cross-target stance detection.SentiHAN introduces an improved hierarchical attention network designed to maximize the use of high-level representations of targets and texts at various fine-grain levels.This model integrates phrase-level combinatorial sentiment knowledge to effectively bridge the knowledge gap between known and unknown targets.By doing so,it enables a comprehensive understanding of stance representations for unknown targets across different sentiments and semantic structures.The model’s ability to leverage sentimentsemantics knowledge enhances its performance in detecting stances that may not be directly observable from the immediate context.Extensive experimental results indicate that SentiHAN significantly outperforms existing benchmark methods in terms of both accuracy and robustness.Moreover,the paper employs ablation studies and visualization techniques to explore the intricate relationship between sentiment and stance.These analyses further confirm the effectiveness of sentence-level combinatorial sentiment knowledge in improving stance detection capabilities. 展开更多
关键词 Cross-target stance detection sentiment analysis commentary-level texts hierarchical attention network
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Game-theoretic approach to power and admission control in hierarchical wireless sensor networks 被引量:2
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作者 Guofang Nan Zhifei Mao Minqiang Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期216-224,共9页
Power efficiency and link reliability are of great impor- tance in hierarchical wireless sensor networks (HWSNs), espe- cially at the key level, which consists of sensor nodes located only one hop away from the sink... Power efficiency and link reliability are of great impor- tance in hierarchical wireless sensor networks (HWSNs), espe- cially at the key level, which consists of sensor nodes located only one hop away from the sink node called OHS. The power and admission control problem in HWSNs is comsidered to improve its power efficiency and link reliability. This problem is modeled as a non-cooperative game in which the active OHSs are con- sidered as players. By applying a double-pricing scheme in the definition of OHSs' utility function, a Nash Equilibrium solution with network properties is derived. Besides, a distributed algorithm is also proposed to show the dynamic processes to achieve Nash Equilibrium. Finally, the simulation results demonstrate the effec- tiveness of the proposed algorithm. 展开更多
关键词 hierarchical network power control admission con- trol game theory double-pricing scheme.
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A Novel Handoff Algorithm for Hierarchical Cellular Networks 被引量:2
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作者 Xiaorong Zhu Mengrong Li +1 位作者 Wenchao Xia Hongbo Zhu 《China Communications》 SCIE CSCD 2016年第8期136-147,共12页
In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile sta... In this paper, we propose a novel speed and service-sensitive handoff algorithm and analytical model for hierarchical cellular networks.First, we use the Gauss-Markov mobility model to predict the speeds of mobile stations, and divide mobile stations into three classes based on the predicted speeds: fast, medium-speed, and slow.Then, according to the mobility classification,network conditions, and service types, mobile stations will be handoff to the proper target networks prior to the deterioration of the currently operating channel. We further develop an analytical model to evaluate the performance of such a hierarchical system with different speed classes and service types. Simulations and analytical results show that the proposed handoff algorithm can significantly improve the network performance in terms of the handoff failure probability, unnecessary handoff probability, and network throughput, comparing with the traditional algorithms. 展开更多
关键词 hierarchical cellular networks handoff algorithm Gauss-Markov mobility model analytical model
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Mixed Hierarchical Networks for Deep Entity Matching
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作者 Chen-Chen Sun De-Rong Shen 《Journal of Computer Science & Technology》 SCIE EI CSCD 2021年第4期822-838,共17页
Entity matching is a fundamental problem of data integration.It groups records according to underlying real-world entities.There is a growing trend of entity matching via deep learning techniques.We design mixed hiera... Entity matching is a fundamental problem of data integration.It groups records according to underlying real-world entities.There is a growing trend of entity matching via deep learning techniques.We design mixed hierarchical deep neural networks(MHN)for entity matching,exploiting semantics from different abstract levels in the record internal hierarchy.A family of attention mechanisms is utilized in different periods of entity matching.Self-attention focuses on internal dependency,inter-attention targets at alignments,and multi-perspective weight attention is devoted to importance discrimination.Especially,hybrid soft token alignment is proposed to address corrupted data.Attribute order is for the first time considered in deep entity matching.Then,to reduce utilization of labeled training data,we propose an adversarial domain adaption approach(DA-MHN)to transfer matching knowledge between different entity matching tasks by maximizing classifier discrepancy.Finally,we conduct comprehensive experimental evaluations on 10 datasets(seven for MHN and three for DA-MHN),which illustrate our two proposed approaches1 superiorities.MHN apparently outperforms previous studies in accuracy,and also each component of MHN is tested.DA-MHN greatly surpasses existing studies in transferability. 展开更多
关键词 entity matching attention mechanism mixed hierarchical neural network(MHN) domain adaption data integration
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Dynamics and control strategies of infectious disease under different scenarios on hierarchical geographical networks
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作者 Xun Ma Ya-Peng Cui +2 位作者 Xiao-Li Yan Shun-Jiang Ni Shi-Fei Shen 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第12期400-410,共11页
Human settlements are embedded in traffic networks with hierarchical structures. In order to understand the spreading mechanism of infectious diseases and deploy control measures, the susceptible-infected-removed spre... Human settlements are embedded in traffic networks with hierarchical structures. In order to understand the spreading mechanism of infectious diseases and deploy control measures, the susceptible-infected-removed spreading process is studied with agents moving globally on the hierarchical geographic network, taking into account agents’ preference for node layers and memory of initial nodes. We investigate the spreading behavior in the case of global infection under different scenarios, including different directions of human flow, different locations of infection source, and different moving behaviors of agents between layers. Based on the above-mentioned analysis, we propose screening strategies based on layer rank and moving distance, and compare their effects on delaying epidemic spreading. We find that in the case of global infection,infection spreads faster in high layers than in low layers, and early infection in high layers and moving to high layers both accelerate epidemic spreading. Travels of high-layer and low-layer residents have different effects on accelerating epidemic spreading, and moving between high and low layers increases the peak value of new infected cases more than moving in the same layer or between adjacent layers. Infection in intermediate nodes enhances the effects of moving of low-layer residents more than the moving of high-layer residents on accelerating epidemic spreading. For screening measures, improving the success rate is more effective on delaying epidemic spreading than expanding the screening range. With the same number of moves screened, screening moves into or out of high-layer nodes combined with screening moves between subnetworks has better results than only screening moves into or out of high-layer nodes, and screening long-distance moves has the worst results when the screening range is small, but it achieves the best results in reducing the peak value of new infected cases when the screening range is large enough. This study probes into the spreading process and control measures under different scenarios on the hierarchical geographical network, and is of great significance for epidemic control in the real world. 展开更多
关键词 disease spreading hierarchical geographical networks screening strategies
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Planning,monitoring and replanning techniques for handling abnormity in HTN-based planning and execution
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作者 KANG Kai CHENG Kai +2 位作者 SHAO Tianhao ZHANG Hongjun ZHANG Ke 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1264-1275,共12页
A framework that integrates planning,monitoring and replanning techniques is proposed.It can devise the best solution based on the current state according to specific objectives and properly deal with the influence of... A framework that integrates planning,monitoring and replanning techniques is proposed.It can devise the best solution based on the current state according to specific objectives and properly deal with the influence of abnormity on the plan execution.The framework consists of three parts:the hierarchical task network(HTN)planner based on Monte Carlo tree search(MCTS),hybrid plan monitoring based on forward and backward and norm-based replanning method selection.The HTN planner based on MCTS selects the optimal method for HTN compound task through pre-exploration.Based on specific objectives,it can identify the best solution to the current problem.The hybrid plan monitoring has the capability to detect the influence of abnormity on the effect of an executed action and the premise of an unexecuted action,thus trigger the replanning.The norm-based replanning selection method can measure the difference between the expected state and the actual state,and then select the best replanning algorithm.The experimental results reveal that our method can effectively deal with the influence of abnormity on the implementation of the plan and achieve the target task in an optimal way. 展开更多
关键词 hierarchical task network Monte carlo tree search(MCTS) PLANNING EXECUTION abnormity
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Dynamic load balancing based on restricted multicast tree in triplet-based hierarchical interconnection network
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作者 刘滨 石峰 +2 位作者 高玉金 计卫星 宋红 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期33-37,共5页
To solve the load balancing problem in a triplet-based hierarchical interconnection network(THIN) system, a dynamic load balancing (DLB)algorithm--THINDLBA, which adopts multicast tree (MT)technology to improve ... To solve the load balancing problem in a triplet-based hierarchical interconnection network(THIN) system, a dynamic load balancing (DLB)algorithm--THINDLBA, which adopts multicast tree (MT)technology to improve the efficiency of interchanging load information, is presented. To support the algorithm, a complete set of DLB messages and a schema of maintaining DLB information in each processing node are designed. The load migration request messages from the heavily loaded node (HLN)are spread along an MT whose root is the HLN. And the lightly loaded nodes(LLNs) covered by the MT are the candidate destinations of load migration; the load information interchanged between the LLNs and the HLN can be transmitted along the MT. So the HLN can migrate excess loads out as many as possible during a one time execution of the THINDLBA, and its load state can be improved as quickly as possible. To avoid wrongly transmitted or redundant DLB messages due to MT overlapping, the MT construction is restricted in the design of the THINDLBA. Through experiments, the effectiveness of four DLB algorithms are compared, and the results show that the THINDLBA can effectively decrease the time costs of THIN systems in dealing with large scale computeintensive tasks more than others. 展开更多
关键词 triplet-based hierarchical interconnection network dynamic load balancing multicast tree
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A P2P Approach to Routing in Hierarchical MANETs
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作者 Thomas Kunz Silas Echegini Babak Esfandiari 《Communications and Network》 2020年第3期99-121,共23页
We present an effective routing solution for the backbone of hierarchical MANETs. </span></span><span><span><span style="font-family:""><span style="font-family:Ver... We present an effective routing solution for the backbone of hierarchical MANETs. </span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">Our solution leverages the storage and retrieval mechanisms of a Distributed Hash Table (DHT) common to many (structured) P2P overlays. Th</span><span style="font-family:Verdana;">e DHT provides routing information in a decentralized fash</span><span style="font-family:Verdana;">ion, while supporting different forms of node and network mobility. We split a flat network into clusters, each having a gateway who participates in a DHT overlay. These g</span><span style="font-family:Verdana;">ateways interconnect the clusters in a backbone network. Two routing </span><span style="font-family:Verdana;">approaches for the backbone are explore</span><span style="font-family:Verdana;">d: floodi</span><span style="font-family:Verdana;">ng and a new solution exploit</span><span style="font-family:Verdana;">ing the storage and retrieval capabilities of a P2P overlay based on a DHT.</span><span style="font-family:Verdana;"> We </span><span style="font-family:Verdana;">implement both approaches in a net</span><span style="font-family:Verdana;">work simulator and thoroughly evaluate th</span><span style="font-family:Verdana;">e performance of the proposed scheme using a range of stati</span><span style="font-family:Verdana;">c and mobile scenarios. We also compare our solution against flooding. The simulation results show that our solution, even in the presence of mobility, achieved well abo</span><span style="font-family:Verdana;">ve 90% success rates and maintained very low and constant round tr</span><span style="font-family:Verdana;">ip times, unlike the flooding approach. In fact, the performance of the proposed </span><span style="font-family:Verdana;">inter-cluster routing solution, in many cases, is comparable to the perfo</span><span style="font-family:Verdana;">rma</span><span style="font-family:Verdana;">nce of the intra-cluster routing case. The advantage of our proposed ap</span><span style="font-family:Verdana;">proach compared to flooding increases as the number of clusters increases, demonstrating the superior scalability of our proposed approach. 展开更多
关键词 MANET ROUTING hierarchical networks DHT P2P Chord OLSR OMNET++
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Strategic games on a hierarchical network model 被引量:2
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作者 Yi-xiao LI Xiao-gang JIN +1 位作者 Fan-sheng KONG Hui-lan LUO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期271-278,共8页
Among complex network models,the hierarchical network model is the one most close to such real networks as world trade web,metabolic network,WWW,actor network,and so on.It has not only the property of power-law degree... Among complex network models,the hierarchical network model is the one most close to such real networks as world trade web,metabolic network,WWW,actor network,and so on.It has not only the property of power-law degree distribution,but also the scaling clustering coefficient property which Barabási-Albert(BA)model does not have.BA model is a model of network growth based on growth and preferential attachment,showing the scale-free degree distribution property.In this paper,we study the evolution of cooperation on a hierarchical network model,adopting the prisoner's dilemma(PD)game and snowdrift game(SG)as metaphors of the interplay between connected nodes.BA model provides a unifying framework for the emergence of cooperation.But interestingly,we found that on hierarchical model,there is no sign of cooperation for PD game,while the fre-quency of cooperation decreases as the common benefit decreases for SG.By comparing the scaling clustering coefficient prop-erties of the hierarchical network model with that of BA model,we found that the former amplifies the effect of hubs.Considering different performances of PD game and SG on complex network,we also found that common benefit leads to cooperation in the evolution.Thus our study may shed light on the emergence of cooperation in both natural and social environments. 展开更多
关键词 Complex network hierarchical network model Barabási-Albert (BA) model Prisoner's dilemma (PD) game Snowdrift game (SG)
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Predicting Complex Word Emotions and Topics through a Hierarchical Bayesian Network 被引量:2
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作者 Kang Xin Ren Fuji 《China Communications》 SCIE CSCD 2012年第3期99-109,共11页
In this paper, we provide a Word Emotion Topic (WET) model to predict the complex word e- motion information from text, and discover the dis- trbution of emotions among different topics. A complex emotion is defined... In this paper, we provide a Word Emotion Topic (WET) model to predict the complex word e- motion information from text, and discover the dis- trbution of emotions among different topics. A complex emotion is defined as the combination of one or more singular emotions from following 8 basic emotion categories: joy, love, expectation, sur- prise, anxiety, sorrow, anger and hate. We use a hi- erarchical Bayesian network to model the emotions and topics in the text. Both the complex emotions and topics are drawn from raw texts, without con- sidering any complicated language features. Our ex- periment shows promising results of word emotion prediction, which outperforms the traditional parsing methods such as the Hidden Markov Model and the Conditional Random Fields(CRFs) on raw text. We also explore the topic distribution by examining the emotion topic variation in an emotion topic diagram. 展开更多
关键词 word emotion classification complex e-motion emotion intensity prediction emotion-topicvariation hierarchical Bayesian network
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Cluster based hierarchical resource searching model in P2P network 被引量:1
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作者 Yang Ruijuan Liu Jian Tian Jingwen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第1期188-194,共7页
For the problem of large network load generated by the Gnutella resource-searching model in Peer to Peer (P2P) network, a improved model to decrease the network expense is proposed, which establishes a duster in P2P... For the problem of large network load generated by the Gnutella resource-searching model in Peer to Peer (P2P) network, a improved model to decrease the network expense is proposed, which establishes a duster in P2P network, auto-organizes logical layers, and applies a hybrid mechanism of directional searching and flooding. The performance analysis and simulation results show that the proposed hierarchical searching model has availably reduced the generated message load and that its searching-response time performance is as fairly good as that of the Gnutella model. 展开更多
关键词 Communication and information system Resource-searching model in P2P network GNUTELLA CLUSTER hierarchical network
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Hunting problems of multi-quadrotor systems via bearing-based hybrid protocols with hierarchical network 被引量:1
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作者 Zhen Xu Xin-Zhi Liu +1 位作者 Qing-Wei Chen Zi-Xing Wu 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期194-202,共9页
Bearing-based hunting protocols commonly adopt a leaderless consensus method,which requests an entire state of the target for each agent and ignores the necessity of collision avoidance.We investigate a hunting proble... Bearing-based hunting protocols commonly adopt a leaderless consensus method,which requests an entire state of the target for each agent and ignores the necessity of collision avoidance.We investigate a hunting problem of multi-quadrotor systems with hybrid bearing protocols,where the quadrotor systems are divided into master and slave groups for reducing the onboard loads and collision avoidance.The masters obtain the entire state of the target,whose hybrid protocols are based on the displacement and bearing constraints to maintain formation and to avoid the collision in the hunting process.However,the slaves’protocols merely depend on the part state of the masters to reduce loads of data transmission.We also investigate the feasibility of receiving the bearing state from machine vision.The simulation results are given to illustrate the effectiveness of the proposed hybrid bearing protocols. 展开更多
关键词 hunting problem multi-quadrotor system bearing constraint hierarchical network
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Soft sensor of chemical processes with large numbers of input parameters using auto-associative hierarchical neural network 被引量:1
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作者 贺彦林 徐圆 +1 位作者 耿志强 朱群雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期138-145,共8页
To explore the problems of monitoring chemical processes with large numbers of input parameters, a method based on Auto-associative Hierarchical Neural Network(AHNN) is proposed. AHNN focuses on dealing with datasets ... To explore the problems of monitoring chemical processes with large numbers of input parameters, a method based on Auto-associative Hierarchical Neural Network(AHNN) is proposed. AHNN focuses on dealing with datasets in high-dimension. AHNNs consist of two parts: groups of subnets based on well trained Autoassociative Neural Networks(AANNs) and a main net. The subnets play an important role on the performance of AHNN. A simple but effective method of designing the subnets is developed in this paper. In this method,the subnets are designed according to the classification of the data attributes. For getting the classification, an effective method called Extension Data Attributes Classification(EDAC) is adopted. Soft sensor using AHNN based on EDAC(EDAC-AHNN) is introduced. As a case study, the production data of Purified Terephthalic Acid(PTA) solvent system are selected to examine the proposed model. The results of the EDAC-AHNN model are compared with the experimental data extracted from the literature, which shows the efficiency of the proposed model. 展开更多
关键词 Soft sensor Auto-associative hierarchical neural network Purified terephthalic acid solvent system MATTER-ELEMENT
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Application and Realization of Hierarchical Network Planning Based on Web 被引量:1
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作者 WUShi-jing GONGZhi-bo YINYong HUANGHe-chao LOUWei-hua 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期839-844,共6页
Making use of Microsoft Visual Studio. NET platform, hierarchical network planning is realized in working procedure time-optimization of the construction by TBM, and hierarchical network graph of the construction by T... Making use of Microsoft Visual Studio. NET platform, hierarchical network planning is realized in working procedure time-optimization of the construction by TBM, and hierarchical network graph of the construction by TBM is drawn based on browser. Then the theory of system realization is discussed, six components of system that can be reused are explained emphatically. The realization of hierarchical network panning in Internet provides available guarantee for controlling rate of progress in large-scale or middle-sized projects. Key words Web - network graph - hierarchical network planning CLC number TU721 Biography: WU Shi-jing (1963-), male, Professor, research direction: equipments management engineering, mechatronics, state monitoring and malfunction diagnostics of machine and electronics equipments. 展开更多
关键词 WEB network graph hierarchical network planning
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Self-organized Criticality in Hierarchical Brain Network
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作者 YANG Qiu-Ying ZHANG Ying-Yue CHEN Tian-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1189-1192,共4页
It is shown that the cortical brain network of the macaque displays a hierarchically clustered organizationand the neuron network shows small-world properties.Now the two factors will be considered in our model and th... It is shown that the cortical brain network of the macaque displays a hierarchically clustered organizationand the neuron network shows small-world properties.Now the two factors will be considered in our model and thedynamical behavior of the model will be studied.We study the characters of the model and find that the distribution ofavalanche size of the model follows power-law behavior. 展开更多
关键词 AVALANCHE self-organized criticality hierarchical network
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A Hierarchical Two-Level Feature Fusion Approach for SMS Spam Filtering
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作者 Hussein Alaa Al-Kabbi Mohammad-Reza Feizi-Derakhshi Saeed Pashazadeh 《Intelligent Automation & Soft Computing》 2024年第4期665-682,共18页
SMS spam poses a significant challenge to maintaining user privacy and security.Recently,spammers have employed fraudulent writing styles to bypass spam detection systems.This paper introduces a novel two-level detect... SMS spam poses a significant challenge to maintaining user privacy and security.Recently,spammers have employed fraudulent writing styles to bypass spam detection systems.This paper introduces a novel two-level detection system that utilizes deep learning techniques for effective spam identification to address the challenge of sophisticated SMS spam.The system comprises five steps,beginning with the preprocessing of SMS data.RoBERTa word embedding is then applied to convert text into a numerical format for deep learning analysis.Feature extraction is performed using a Convolutional Neural Network(CNN)for word-level analysis and a Bidirectional Long Short-Term Memory(BiLSTM)for sentence-level analysis.The two-level feature extraction enables a complete understanding of individual words and sentence structure.The novel part of the proposed approach is the Hierarchical Attention Network(HAN),which fuses and selects features at two levels through an attention mechanism.The HAN can deal with words and sentences to focus on the most pertinent aspects of messages for spam detection.This network is productive in capturing meaningful features,considering both word-level and sentence-level semantics.In the classification step,the model classifies the messages into spam and ham.This hybrid deep learning method improve the feature representation,and enhancing the model’s spam detection capabilities.By significantly reducing the incidence of SMS spam,our model contributes to a safer mobile communication environment,protecting users against potential phishing attacks and scams,and aiding in compliance with privacy and security regulations.This model’s performance was evaluated using the SMS Spam Collection Dataset from the UCI Machine Learning Repository.Cross-validation is employed to consider the dataset’s imbalanced nature,ensuring a reliable evaluation.The proposed model achieved a good accuracy of 99.48%,underscoring its efficiency in identifying SMS spam. 展开更多
关键词 SMS spam detection hierarchical attention network text classification natural language processing
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DNA Sequence Classification Based on the Side Chain Radical Polarity of Amino Acids
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作者 王显金 《Agricultural Science & Technology》 CAS 2014年第5期751-755,共5页
The features of DNA sequence fragments were extracted from the distribution density of the condons in the individual cases of DNA sequence fragments. Based on the polarity of side chain radicals of amino acids molecul... The features of DNA sequence fragments were extracted from the distribution density of the condons in the individual cases of DNA sequence fragments. Based on the polarity of side chain radicals of amino acids molecules, the amino acids were classified into five categories, and the frequencies of these five categories were calculated. This kind of feature extraction based on the biological meanings not only took the content of basic groups into consideration, but also considered the marshal ing sequence of the basic groups. The hierarchical clustering analysis and BP neural network were used to classify the DNA sequence fragments. The results showed that the classification results of these two kinds of algo-rithms not only had high accuracy, but also had high consistence, indicating that this kind of feature extraction was superior over the traditional feature extraction which only took the features of basic groups into consideration. 展开更多
关键词 CODON FREQUENCY hierarchical clustering analysis BP neural network
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High N-doped hierarchical porous carbon networks with expanded interlayers for efficient sodium storage 被引量:12
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作者 Dongqin Su Man Huang +5 位作者 Junhao Zhang Xingmei Guo Jiale Chen Yanchun Xue Aihua Yuan Qinghong Kong 《Nano Research》 SCIE EI CAS CSCD 2020年第10期2862-2868,共7页
Sodium-ion batteries (SIBs) have been attracting considerable attention as a promising candidate for large-scale energy storage because of the abundance and low-cost of sodium resources. However, lack of appropriate a... Sodium-ion batteries (SIBs) have been attracting considerable attention as a promising candidate for large-scale energy storage because of the abundance and low-cost of sodium resources. However, lack of appropriate anode materials impedes further applications. Herein, a novel self-template strategy is designed to synthesize uniform flowerlike N-doped hierarchical porous carbon networks (NHPCN) with high content of N (15.31 at.%) assembled by ultrathin nanosheets via a self-synthesized single precursor and subsequent thermal annealing. Relying on the synergetic coordination of benzimidazole and 2-methylimidazole with metal ions to produce a flowerlike network, a self-formed single precursor can be harvested. Due to the structural and compositional advantages, including the high N doping, the expanded interlayer spacing, the ultrathin two-dimensional nano-sized subunits, and the three-dimensional porous network structure, these unique NHPCN flowers deliver ultrahigh reversible capacities of 453.7 mAh·g^−1 at 0.1 A·g^−1 and 242.5 mAh·g^−1 at 1 A·g^−1 for 2,500 cycles with exceptional rate capability of 5 A·g^−1 with reversible capacities of 201.2 mAh·g^−1. The greatly improved sodium storage performance of NHPCN confirms the importance of reasonable engineering and synthesis of hierarchical carbon with unique structures. 展开更多
关键词 hierarchical porous carbon networks high N doping expanded interlayer spacing ANODE sodium-ion batteries
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