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Sum-Rate Maximization in Active RIS-Assisted Multi-Antenna WPCN
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作者 Jiang Jie Lyu Bin +1 位作者 Chen Pengcheng Yang Zhen 《China Communications》 SCIE CSCD 2024年第6期23-39,共17页
In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both... In this paper,we propose an active reconfigurable intelligent surface(RIS)enabled hybrid relaying scheme for a multi-antenna wireless powered communication network(WPCN),where the active RIS is employed to assist both wireless energy transfer(WET)from the power station(PS)to energyconstrained users and wireless information transmission(WIT)from users to the receiving station(RS).For further performance enhancement,we propose to employ both transmit beamforming at the PS and receive beamforming at the RS.We formulate a sumrate maximization problem by jointly optimizing the RIS phase shifts and amplitude reflection coefficients for both the WET and the WIT,transmit and receive beamforming vectors,and network resource allocation.To solve this non-convex problem,we propose an efficient alternating optimization algorithm with the linear minimum mean squared error criterion,semidefinite relaxation(SDR)and successive convex approximation techniques.Specifically,the tightness of applying the SDR is proved.Simulation results demonstrate that our proposed scheme with 10 reflecting elements(REs)and 4 antennas can achieve 17.78%and 415.48%performance gains compared to the single-antenna scheme with 10 REs and passive RIS scheme with 100 REs,respectively. 展开更多
关键词 active reconfigurable intelligent surface BEAMFORMING sum-rate maximization wireless powered communication network
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Predictive active control of building structures using LQR and artificial intelligence
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作者 Nirmal S.Mehta Vishisht Bhaiya +1 位作者 K.A.Patel Ehsan Noroozinejad Farsangi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第2期489-502,共14页
This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response reduction.Based on the expected weighting matrices,the LQR algorithm is... This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response reduction.Based on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the structure.The responses are determined by numerically analyzing the governing equation of motion using the state-space approach.For training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting matrices.To study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage reductions.Furthermore,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled responses.The trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage reduction.Based on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using LQRNN.Moreover,the LQRNN algorithm can replace conventional LQR control with the use of an active control system. 展开更多
关键词 active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor RESILIENCE
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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs
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作者 Lianghao Hua Jianfeng Zhang +1 位作者 Dejie Li Xiaobo Xi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2129-2157,共29页
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej... With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance. 展开更多
关键词 Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm
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Analysis of Lavandulyl Flavonoids from Sophora flavescens with Antiinflammatory Activity Based on Molecular Network Technology
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作者 Yan LIN Bo TU +1 位作者 Shanggao LIAO Minghui HE 《Medicinal Plant》 2024年第2期1-5,14,共6页
[Objectives]This study was conducted to screen lavandulyl flavonoids with anti-inflammatory activity from Sophora flavescens.[Methods]35 compounds were screened from traditional Chinese medicine S.flavescens using the... [Objectives]This study was conducted to screen lavandulyl flavonoids with anti-inflammatory activity from Sophora flavescens.[Methods]35 compounds were screened from traditional Chinese medicine S.flavescens using the nitric oxide(NO)anti-inflammatory activity model.[Results]Five components,8(xanthohumol),13(kurarinol),27(4-methoxysalicylic acid),28(b-resorcic acid)and 30(b-resorcic acid),exhibited significant anti-inflammatory activity,with IC 50 values of 5.99,4.76,6.96,3.41 and 5.22μM,respectively.Especially,8(xanthohumol)and 13(kurarinol)were typical lavandulyl flavonoids in S.flavescens,which were worth further exploration.Furthermore,UPLC-Q-Exactive and GNPS molecular networking technique were used for rapid analysis of lavandulyl flavonoids from S.flavescens.A total of 15 components were identified.[Conclusions]This work lays a theoretical foundation for further separation and analysis of lavandulyl flavonoids with anti-inflammatory activity from S.flavescens. 展开更多
关键词 Sophora flavescens Molecular network Anti-inflammatory activity Lavandulyl flavonoids
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Active components of Bupleuri Radix in the treatment of schizophrenia analyzed by network pharmacology and clinical verification
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作者 Jiang Xiao Jun Guo +6 位作者 Xin-Yu Zheng Wen Sun Qiu-Xiang Ning Li Tang Jian-Ying Xiao Liang Li Ping Yang 《Traditional Medicine Research》 2023年第11期14-22,共9页
Background:Bupleuri Radix is a common Chinese medicinal material in traditional Chinese medicine.Currently,the therapeutic effect of treating schizophrenia is relatively well understood.However,there are fewer studies... Background:Bupleuri Radix is a common Chinese medicinal material in traditional Chinese medicine.Currently,the therapeutic effect of treating schizophrenia is relatively well understood.However,there are fewer studies examining the underlying mechanisms of its treatment.The objective of the study was to investigate the primary mechanisms of Bupleuri Radix in treating schizophrenia through network pharmacology and clinical validation.Method:Network pharmacology revealed possible molecular mechanisms,followed by clinical verification.Sixty-seven schizophrenia patients undergoing treatment at the Hunan Brain Hospital between October and November 2022 were recruited and randomly divided into the olanzapine group and the olanzapine+Bupleuri Radix group.Additionally,32 healthy people undergoing physical examinations during the same period were included as the control group.The patient’s positive and negative symptom scale scores were compared.qPCR was used to detect the mRNA expression levels of ESR1,mTOR,EIF4E,and SMAD4 in peripheral blood.Results:Through network pharmacological analysis,it was concluded in this study that Bupleuri Radix might regulate the mTOR,PI3K-Akt,and HIF-1 signaling pathways.Clinical experiments indicated that compared with before treatment,the positive and negative symptom scale scores and total scores of the two treatment groups were significantly decreased after treatment(P<0.01).In addition,the positive and negative symptom scale scores and total scores in the olanzapine+Bupleuri Radix group were significantly decreased(P<0.01)compared to the olanzapine group after treatment.Before treatment,ESR1 mRNA expression levels in peripheral blood were significantly higher in the two treatment groups than in the control group,whereas the mRNA expression levels of mTOR,EIF4E,and SMAD4 in peripheral blood were significantly lower(P<0.01).The mRNA expression levels of mTOR,EIF4E,and SMAD4 in peripheral blood were significantly higher after therapy than before treatment,whereas the mRNA expression levels of ESR1 in peripheral blood were significantly lower(P<0.01).After therapy,the olanzapine+Bupleuri Radix group’s mRNA expression levels of mTOR,EIF4E,and SMAD4 were significantly higher than those of the olanzapine group,whereas the mRNA expression levels of ESR1 were significantly lower(P<0.01).Conclusion:The mechanism of Bupleuri Radix’s therapeutic efficacy in schizophrenia may involve the up-regulation of mTOR,EIF4E,and SMAD4 mRNA expression and the down-regulation of ESR1 mRNA expression in peripheral blood. 展开更多
关键词 SCHIZOPHRENIA Bupleuri Radix network pharmacology clinical verification active components
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Optimal Location and Sizing of Distributed Generator via Improved Multi-Objective Particle Swarm Optimization in Active Distribution Network Considering Multi-Resource
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作者 Guobin He Rui Su +5 位作者 Jinxin Yang Yuanping Huang Huanlin Chen Donghui Zhang Cangtao Yang Wenwen Li 《Energy Engineering》 EI 2023年第9期2133-2154,共22页
In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distribut... In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively. 展开更多
关键词 active distribution network multi-resource penetration operation enhancement particle swarm optimization multi-objective optimization
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Blockchain-Based Power Transaction Method for Active Distribution Network
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作者 Fei Zeng Zhinong Wei +1 位作者 Haiteng Han Yang Chen 《Energy Engineering》 EI 2023年第5期1067-1080,共14页
A blockchain-based power transaction method is proposed for Active Distribution Network(ADN),considering the poor security and high cost of a centralized power trading system.Firstly,the decentralized blockchain struc... A blockchain-based power transaction method is proposed for Active Distribution Network(ADN),considering the poor security and high cost of a centralized power trading system.Firstly,the decentralized blockchain structure of the ADN power transaction is built and the transaction information is kept in blocks.Secondly,considering the transaction needs between users and power suppliers in ADN,an energy request mechanism is proposed,and the optimization objective function is designed by integrating cost aware requests and storage aware requests.Finally,the particle swarm optimization algorithm is used for multi-objective optimal search to find the power trading scheme with the minimum power purchase cost of users and the maximum power sold by power suppliers.The experimental demonstration of the proposed method based on the experimental platform shows that when the number of participants is no more than 10,the transaction delay time is 0.2 s,and the transaction cost fluctuates at 200,000 yuan,which is better than other comparison methods. 展开更多
关键词 Blockchain active distribution network power transaction energy request mechanism particle swarm optimization algorithm
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Active Network研究综述 被引量:1
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作者 夏正友 钟亦平 张世永 《小型微型计算机系统》 CSCD 北大核心 2003年第10期1821-1824,共4页
介绍了两种实现 Active Network方法 ,描述 Active Network结构与组成、Active Network封装协议和 ActiveNetwork编程模型 .讨论国内外对 Active Network的研究成果和进展 .在该文最后对 Active network研究作了总结 。
关键词 active-network 离散方法 集成方法 综述 封装协议 编程模型
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Active Network系统的结构分析与研究
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作者 马燕 《计算机科学》 CSCD 北大核心 2002年第4期89-92,共4页
现有的网络系统基于"端到端"的模型体系,是1984年由H.Salzer、D.Reed和D.Clark提出来的.在这种网络中,相关的计算和控制是在发送和接收"端点"进行的,在网络的结点上不对包进行处理.虽然在网络中路由器和交换机可以... 现有的网络系统基于"端到端"的模型体系,是1984年由H.Salzer、D.Reed和D.Clark提出来的.在这种网络中,相关的计算和控制是在发送和接收"端点"进行的,在网络的结点上不对包进行处理.虽然在网络中路由器和交换机可以改变包头,但是对用户的数据不做任何处理,因此目前的网络系统又称为是"被动网络". 展开更多
关键词 主动网络 计算机网络 路由器 交换机 activenetwork系统 结构分析
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Sensor Scheduling for Target Tracking in Networks of Active Sensors 被引量:7
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作者 XIAO Wen-Dong WU Jian-Kang +1 位作者 XIE Li-Hua DONG Liang 《自动化学报》 EI CSCD 北大核心 2006年第6期922-928,共7页
Wireless sensor network (WSN) of active sensors suffers from serious inter-sensor interference (ISI) and imposes new design and implementation challenges. In this paper, based on the ultrasonic sensor network, two tim... Wireless sensor network (WSN) of active sensors suffers from serious inter-sensor interference (ISI) and imposes new design and implementation challenges. In this paper, based on the ultrasonic sensor network, two time-division based distributed sensor scheduling schemes are proposed to deal with ISI by scheduling sensors periodically and adaptively respectively. Extended Kalman filter (EKF) is used as the tracking algorithm in distributed manner. Simulation results show that the adaptive sensor scheduling scheme can achieve superior tracking accuracy with faster tracking convergence speed. 展开更多
关键词 Wireless sensor network sensor scheduling target tracking active sensor
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Active Vibration Isolation of Micro-Manufacturing Platform Based on Neural Network 被引量:4
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作者 ZHANG Chun-liang, MEI De-qing, CHEN Zi-chen (Institute of Production Engineering, Zhejiang University, Hangzhou 310027, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期67-68,共2页
The micromation and precision of the Micro-Electromechanical System demand that its manufacturing, measuring and assembling must work in a micro-manufacturing platform with good ability to isolate vibrations. This pap... The micromation and precision of the Micro-Electromechanical System demand that its manufacturing, measuring and assembling must work in a micro-manufacturing platform with good ability to isolate vibrations. This paper develops a vibration isolation system of micro-manufacturing platform. The brains of many kinds of birds can isolate vibrations well, such as woodpecker’s brain. When a woodpecker pecks the wood at the speed as 1.6 times as the velocity of sound, its brain will tolerate the wallop 1 500 times of the weight of itself without any damage. The isolation mechanics and organic texture of woodpecker’s brain that has good isolation characteristics were studied. A structure model of vibration isolation system for the micro-manufacturing platform is established based on the bionics of the bird’s brain vibration isolation mechanism. In order to isolate effectively the high frequency vibrations from the ground, a rubber layer is used to isolate vibrations passively between the micro-manufacturing platform’s pedestal and the ground. This layer corresponds to the cartilage and muscles in the outer meninges of the bird’s brain. The active vibration isolation technique is adopted to isolate vibrations between the micro-manufacturing platform and the pedestal. Air springs are used as elastic components, which correspond to the interspaces between the outer meninges and the encephala of the bird’s brain. Actuators are made of giant magnetostrictive material, and it corresponds to the nerves and neural muscles linking the meninges and the encephala. The actuators and air springs are arranged vertically in parallel to make use of the giant magnetostrictive actuators effectively. The air springs support almost all weight of the micro-manufacturing platform and the giant magnetostrictive actuators support almost no weight. In order to realize high performance to isolate complex micro-vibration, the control method using a three-layer neural network is presented. This vibration control system takes into account the floor disturbance and the direct disturbance acting on the micro-manufacturing platform. The absolute acceleration of the micro-manufacturing platform is used as the performance index of vibration control. The performance of the control system is tested by numerical simulation. Simulation results show that the active vibration isolation system has good isolation performance against the floor disturbance and the direct disturbance acting on the micro-manufacturing platform in all the frequency range. 展开更多
关键词 micro-manufacturing platform active vibration isolation bionic mechanics neural network
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Network Pharmacology-based Research of Active Components of Albiziae Flos and Mechanisms of Its Antidepressant Effect 被引量:8
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作者 Wei-chen XIONG He-zhen WU +5 位作者 Yi-yi XIONG Bo LIU Zhou-tao XIE Song-tao WU Yun-feng YAO Yan-fang YANG 《Current Medical Science》 SCIE CAS 2020年第1期123-129,共7页
Albiziae Flos(AF)has been experimentally proven to have an antidepressant effect.However,due to the complexity of botanical ingredients,the exact pharmacological mechanism of action of AF in depression has not been co... Albiziae Flos(AF)has been experimentally proven to have an antidepressant effect.However,due to the complexity of botanical ingredients,the exact pharmacological mechanism of action of AF in depression has not been completely deciphered.This study used the network pharmacology method to construct a component-target-pathway network to explore the active components and potential mechanisms of action of AF.The methods included collection and screening of chemical components,prediction of depression-associated targets of the active components,gene enrichment,and network construction and analysis.Quercetin and 4 other active components were found to exert an tidepressant effects mainly via monoaminergic neurotransmitters and cAMP signaling and neuroactive ligand・wceptor interaction pathways.DRD2,HTR1 A,and SLC6A4 were identified as important targets of the studied bioactive components of AF.This network pharmacology analysis provides guidance for further study of the antidepressant mechanism of AF. 展开更多
关键词 Albiziae Flos network pharmacology ANTIDEPRESSANT active components signaling pathways
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Guaranteed Cost Active Fault-tolerant Control of Networked Control System with Packet Dropout and Transmission Delay 被引量:5
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作者 Xiao-Yuan Luo Mei-Jie Shang +1 位作者 Cai-Lian Chen Xin-Ping Guan 《International Journal of Automation and computing》 EI 2010年第4期509-515,共7页
The problem of guaranteed cost active fault-tolerant controller (AFTC) design for networked control systems (NCSs) with both packet dropout and transmission delay is studied in this paper. Considering the packet d... The problem of guaranteed cost active fault-tolerant controller (AFTC) design for networked control systems (NCSs) with both packet dropout and transmission delay is studied in this paper. Considering the packet dropout and transmission delay, a piecewise constant controller is adopted. With a guaranteed cost function, optimal controllers whose number is equal to the number of actuators are designed, and the design process is formulated as a convex optimal problem that can be solved by existing software. The control strategy is proposed as follows: when actuator failures appear, the fault detection and isolation unit sends out the information to the controller choosing strategy, and then the optimal stabilizing controller with the smallest guaranteed cost value is chosen. Two illustrative examples are given to demonstrate the effectiveness of the proposed approach. By comparing with the existing methods, it can be seen that our method has a better performance. 展开更多
关键词 networked control system (NCS) packet dropout transmission delay active fault-tolerant control (AFTC) guaranteed cost controller.
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Multi-Path Routing and Resource Allocation in Active Network 被引量:2
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作者 XUWu-ping YANPu-liu WUMing 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第2期398-404,共7页
An algorithm of traffic distribution called active multi-path routing (AMR)in active network is proposed. AMR adopts multi-path routing and applies nonlinear optimizeapproximate method to distribute network traffic am... An algorithm of traffic distribution called active multi-path routing (AMR)in active network is proposed. AMR adopts multi-path routing and applies nonlinear optimizeapproximate method to distribute network traffic among multiple paths. It is combined to bandwidthresource allocation and the congestion restraint mechanism to avoid congestion happening and worsen.So network performance can be improved greatly. The frame of AMR includes adaptive trafficallocation model, the conception of supply bandwidth and its' allocation model, the principle ofcongestion restraint and its' model, and the implement of AMR based on multi-agents system in activenetwork. Through simulations, AMR has distinct effects on network performance. The results show AMRisa valid traffic regulation algorithm. 展开更多
关键词 multi-path routing resource allocation congestion control active network multi-agent system
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Neural Network-Based Active Control for Offshore Platforms 被引量:2
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作者 周亚军 赵德有 《海洋工程:英文版》 2003年第3期461-468,共8页
A new active control scheme, based on neural network, for the suppression of oscillation in multiple-degree-of-freedom (MDOF) offshore platforms, is studied in this paper. With the main advantages of neural network, i... A new active control scheme, based on neural network, for the suppression of oscillation in multiple-degree-of-freedom (MDOF) offshore platforms, is studied in this paper. With the main advantages of neural network, i.e. the inherent robustness, fault tolerance, and generalized capability of its parallel massive interconnection structure, the active structural control of offshore platforms under random waves is accomplished by use of the BP neural network model. The neural network is trained offline with the data generated from numerical analysis, and it simulates the process of Classical Linear Quadratic Regular Control for the platform under random waves. After the learning phase, the trained network has learned about the nonlinear dynamic behavior of the active control system, and is capable of predicting the active control forces of the next time steps. The results obtained show that the active control is feasible and effective, and it finally overcomes time delay owing to the robustness, fault tolerance, and generalized capability of artificial neural network. 展开更多
关键词 active control offshore platform neural network time delay VIBRATION
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A FUZZY-LOGIC CONTROL ALGORITHM FOR ACTIVE QUEUE MANAGEMENT IN IP NETWORKS 被引量:10
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作者 Liu Weiyan Zhang Shunyi +1 位作者 Zhang Mu Liu Tao 《Journal of Electronics(China)》 2008年第1期102-107,共6页
Active Queue Management (AQM) is an active research area in the Internet community. Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its ave... Active Queue Management (AQM) is an active research area in the Internet community. Random Early Detection (RED) is a typical AQM algorithm, but it is known that it is difficult to configure its parameters and its average queue length is closely related to the load level. This paper proposes an effective fuzzy congestion control algorithm based on fuzzy logic which uses the pre- dominance of fuzzy logic to deal with uncertain events. The main advantage of this new congestion control algorithm is that it discards the packet dropping mechanism of RED, and calculates packet loss according to a preconfigured fuzzy logic by using the queue length and the buffer usage ratio. Theo- retical analysis and Network Simulator (NS) simulation results show that the proposed algorithm achieves more throughput and more stable queue length than traditional schemes. It really improves a router's ability in network congestion control in IP network. 展开更多
关键词 Congestion control Fuzzy logic AQM active Queue Management) RED (Random Early Detection) IP network
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FIXED/PREASSIGNED-TIME SYNCHRONIZATION OF QUATERNION-VALUED NEURAL NETWORKS INVOLVING DELAYS AND DISCONTINUOUS ACTIVATIONS: A DIRECT APPROACH
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作者 魏琬璐 胡成 +1 位作者 于娟 蒋海军 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1439-1461,共23页
The fixed-time synchronization and preassigned-time synchronization are investigated for a class of quaternion-valued neural networks with time-varying delays and discontinuous activation functions. Unlike previous ef... The fixed-time synchronization and preassigned-time synchronization are investigated for a class of quaternion-valued neural networks with time-varying delays and discontinuous activation functions. Unlike previous efforts that employed separation analysis and the real-valued control design, based on the quaternion-valued signum function and several related properties, a direct analytical method is proposed here and the quaternion-valued controllers are designed in order to discuss the fixed-time synchronization for the relevant quaternion-valued neural networks. In addition, the preassigned-time synchronization is investigated based on a quaternion-valued control design, where the synchronization time is preassigned and the control gains are finite. Compared with existing results, the direct method without separation developed in this article is beneficial in terms of simplifying theoretical analysis, and the proposed quaternion-valued control schemes are simpler and more effective than the traditional design, which adds four real-valued controllers. Finally, two numerical examples are given in order to support the theoretical results. 展开更多
关键词 fixed-time synchronization preassigned-time synchronization quaternion-valued neural networks discontinuous activation direct analysis method
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Adaptive Fixed-Time Synchronization of Delayed Memristor-Based Neural Networks with Discontinuous Activations
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作者 Tianyuan Jia Xiangyong Chen +2 位作者 Xiurong Yao Feng Zhao Jianlong Qiu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第1期221-239,共19页
Fixed-time synchronization(FTS)of delayed memristor-based neural networks(MNNs)with discontinuous activations is studied in this paper.Both continuous and discontinuous activations are considered forMNNs.And the mixed... Fixed-time synchronization(FTS)of delayed memristor-based neural networks(MNNs)with discontinuous activations is studied in this paper.Both continuous and discontinuous activations are considered forMNNs.And the mixed delays which are closer to reality are taken into the system.Besides,two kinds of control schemes are proposed,including feedback and adaptive control strategies.Based on some lemmas,mathematical inequalities and the designed controllers,a few synchronization criteria are acquired.Moreover,the upper bound of settling time(ST)which is independent of the initial values is given.Finally,the feasibility of our theory is attested by simulation examples. 展开更多
关键词 Memristor-based neural networks fixed-time synchronization mixed delays discontinuous activations adaptive control
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Deep Pyramidal Residual Network for Indoor-Outdoor Activity Recognition Based on Wearable Sensor
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作者 Sakorn Mekruksavanich Narit Hnoohom Anuchit Jitpattanakul 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期2669-2686,共18页
Recognition of human activity is one of the most exciting aspects of time-series classification,with substantial practical and theoretical impli-cations.Recent evidence indicates that activity recognition from wearabl... Recognition of human activity is one of the most exciting aspects of time-series classification,with substantial practical and theoretical impli-cations.Recent evidence indicates that activity recognition from wearable sensors is an effective technique for tracking elderly adults and children in indoor and outdoor environments.Consequently,researchers have demon-strated considerable passion for developing cutting-edge deep learning sys-tems capable of exploiting unprocessed sensor data from wearable devices and generating practical decision assistance in many contexts.This study provides a deep learning-based approach for recognizing indoor and outdoor movement utilizing an enhanced deep pyramidal residual model called Sen-PyramidNet and motion information from wearable sensors(accelerometer and gyroscope).The suggested technique develops a residual unit based on a deep pyramidal residual network and introduces the concept of a pyramidal residual unit to increase detection capability.The proposed deep learning-based model was assessed using the publicly available 19Nonsens dataset,which gathered motion signals from various indoor and outdoor activities,including practicing various body parts.The experimental findings demon-strate that the proposed approach can efficiently reuse characteristics and has achieved an identification accuracy of 96.37%for indoor and 97.25%for outdoor activity.Moreover,comparison experiments demonstrate that the SenPyramidNet surpasses other cutting-edge deep learning models in terms of accuracy and F1-score.Furthermore,this study explores the influence of several wearable sensors on indoor and outdoor action recognition ability. 展开更多
关键词 Human activity recognition deep learning wearable sensors indoor and outdoor activity deep pyramidal residual network
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Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition 被引量:1
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作者 Yi-Chun Lai Shu-Yin Chiang +1 位作者 Yao-Chiang Kan Hsueh-Chun Lin 《Computers, Materials & Continua》 SCIE EI 2024年第6期3783-3803,共21页
Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation tracking.This study intr... Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation tracking.This study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in HAR.The analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the models.Additionally,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDM database,renowned for its challenging features,supports the framework’s resilience and adaptability.The ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVM),and random forest(RF),for data training.In contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature extraction.Furthermore,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model performance.The best accuracies of the ANFIS,SVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,respectively.Comparative analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVM,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,respectively.Finally,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research findings.In conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications. 展开更多
关键词 Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination
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