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Weak node protection to maximize the lifetime of wirelesssensor networks 被引量:2
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作者 MAO Yuxing ZHAO Huiyuan YAN Dongmei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期693-706,共14页
Wireless sensor networks (WSN) provide an approachto collecting distributed monitoring data and transmiting them tothe sink node. This paper proposes a WSN-based multi-hop networkinfrastructure, to increase network ... Wireless sensor networks (WSN) provide an approachto collecting distributed monitoring data and transmiting them tothe sink node. This paper proposes a WSN-based multi-hop networkinfrastructure, to increase network lifetime by optimizing therouting strategy. First, a network model is established, an operatingcontrol strategy is devised, and energy consumption characteristicsare analyzed. Second, a fast route-planning algorithm isproposed to obtain the original path that takes into account the remainingenergy of communicating nodes and the amount of energyconsumed in data transmission. Next, considering the amount ofenergy consumed by an individual node and the entire network,a criterion function is established to describe node performanceand to evaluate data transmission ability. Finally, a route optimizingalgorithm is proposed to increase network lifetime by adjusting thetransmission route in protection of the weak node (the node withlow transmission ability). Simulation and comparison experimentalresults demonstrate the good performance of the proposed algorithmsto increase network lifetime. 展开更多
关键词 wireless sensor network (WsN) multi-hop transmission ROUTING network lifetime energy efficient
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rTMS Improves Cognitive Function and Brain Network Connectivity in Patients With Alzheimer’s Disease
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作者 XU Gui-Zhi LIU Lin +4 位作者 GUO Miao-Miao WANG Tian GAO Jiao-Jiao JI Yong WANG Pan 《生物化学与生物物理进展》 北大核心 2025年第8期2131-2145,共15页
Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,n... Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,neural oscillatory dynamics,and brain network reorganization remain unclear.This investigation seeks to systematically evaluate the therapeutic potential of rTMS as a non-invasive neuromodulatory intervention through a multimodal framework integrating clinical assessments,molecular profiling,and neurophysiological monitoring.Methods In this prospective double-blind trial,12 AD patients underwent a 14-day protocol of 20 Hz rTMS,with comprehensive multimodal assessments performed pre-and postintervention.Cognitive functioning was quantified using the mini-mental state examination(MMSE)and Montreal cognitive assessment(MOCA),while daily living capacities and neuropsychiatric profiles were respectively evaluated through the activities of daily living(ADL)scale and combined neuropsychiatric inventory(NPI)-Hamilton depression rating scale(HAMD).Peripheral blood biomarkers,specifically Aβ1-40 and phosphorylated tau(p-tau181),were analyzed to investigate the effects of rTMS on molecular metabolism.Spectral power analysis was employed to investigate rTMS-induced modulations of neural rhythms in AD patients,while brain network analyses incorporating topological properties were conducted to examine stimulus-driven network reorganization.Furthermore,systematic assessment of correlations between cognitive scale scores,blood biomarkers,and network characteristics was performed to elucidate cross-modal therapeutic associations.Results Clinically,MMSE and MOCA scores improved significantly(P<0.05).Biomarker showed that Aβ1-40 level increased(P<0.05),contrasting with p-tau181 reduction.Moreover,the levels of Aβ1-40 were positively correlated with MMSE and MOCA scores.Post-intervention analyses revealed significant modulations in oscillatory power,characterized by pronounced reductions in delta(P<0.05)and theta bands(P<0.05),while concurrent enhancements were observed in alpha,beta,and gamma band activities(all P<0.05).Network analysis revealed frequency-specific reorganization:clustering coefficients were significantly decreased in delta,theta,and alpha bands(P<0.05),while global efficiency improvement was exclusively detected in the delta band(P<0.05).The alpha band demonstrated concurrent increases in average nodal degree(P<0.05)and characteristic path length reduction(P<0.05).Further research findings indicate that the changes in the clinical scale HAMD scores before and after rTMS stimulation are negatively correlated with the changes in the blood biomarkers Aβ1-40 and p-tau181.Additionally,the changes in the clinical scales MMSE and MoCA scores were negatively correlated with the changes in the node degree of the alpha frequency band and negatively correlated with the clustering coefficient of the delta frequency band.However,the changes in MMSE scores are positively correlated with the changes in global efficiency of both the delta and alpha frequency bands.Conclusion 20 Hz rTMS targeting dorsolateral prefrontal cortex(DLPFC)significantly improves cognitive function and enhances the metabolic clearance ofβ-amyloid and tau proteins in AD patients.This neurotherapeutic effect is mechanistically associated with rTMS-mediated frequency-selective neuromodulation,which enhances the connectivity of oscillatory networks through improved neuronal synchronization and optimized topological organization of functional brain networks.These findings not only support the efficacy of rTMS as an adjunctive therapy for AD but also underscore the importance of employing multiple assessment methods—including clinical scales,blood biomarkers,and EEG——in understanding and monitoring the progression of AD.This research provides a significant theoretical foundation and empirical evidence for further exploration of rTMS applications in AD treatment. 展开更多
关键词 transcranial magnetic stimulation Alzheimer’s disease power spectral density ELECTROENCEPHALOGRAM brain functional network
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一种基于改进D-S证据的智慧水利网络安全态势评估方法
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作者 夏卓群 周子豪 +1 位作者 邓斌 康琛 《计算机科学》 北大核心 2025年第S1期938-943,共6页
智慧水利是国家关键信息基础设施的重要行业和领域。网络安全态势评估技术的研究,为智慧水利的数据保护和网络安全建设提供了有力支撑。针对智慧水利网络模型特点以及基于单一D-S证据理论的网络安全态势评估模型中存在着主观依赖性、证... 智慧水利是国家关键信息基础设施的重要行业和领域。网络安全态势评估技术的研究,为智慧水利的数据保护和网络安全建设提供了有力支撑。针对智慧水利网络模型特点以及基于单一D-S证据理论的网络安全态势评估模型中存在着主观依赖性、证据冲突大的问题,提出了一种基于改进D-S证据理论的智慧水利态势评估方法。首先,面对海量水利数据,使用深度自编码器对数据进行特征学习和过滤降维处理。然后,将处理后的数据交由深度神经网络进行二分类和多分类计算,并将结果融合,得出基本概率分配函数值,其将作为D-S证据理论的输入。最后,通过D-S证据理论的融合规则得到最终的网络安全态势评估结果。实验结果表明,相较于传统态势评估模型,所提方法能够在提升客观性的情况下,保持较高的准确性。 展开更多
关键词 智慧水利 网络安全态势感知 D-s证据理论 深度自编码器 深度神经网络
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Node deployment strategy optimization for wireless sensor network with mobile base station 被引量:7
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作者 龙军 桂卫华 《Journal of Central South University》 SCIE EI CAS 2012年第2期453-458,共6页
The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytica... The optimization of network performance in a movement-assisted data gathering scheme was studied by analyzing the energy consumption of wireless sensor network with node uniform distribution. A theoretically analytical method for avoiding energy hole was proposed. It is proved that if the densities of sensor nodes working at the same time are alternate between dormancy and work with non-uniform node distribution. The efficiency of network can increase by several times and the residual energy of network is nearly zero when the network lifetime ends. 展开更多
关键词 wireless sensor network mobile base station network optimization energy consumption balancing density ratio of sensor node network lifetime
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5米S-SAR卫星固态有源馈电网络设计与实现
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作者 赵海洋 吕慎刚 +2 位作者 李阳斌 刘洪斌 郑新 《航天器工程》 北大核心 2025年第3期103-110,共8页
针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、... 针对5米S频段合成孔径雷达(S-SAR)卫星对有源馈电系统提出的高功率、高效率、高可靠性及多极化等应用需求,文章设计了一种固态有源馈电网络,采用相控阵馈源体制,在原集中式馈电系统的基础上,引入相控阵的设计理念,通过收发(T/R)组件、波束控制单元等来实现射频大功率有源馈电和多极化工作模式。通过对氮化镓(GaN)化合物半导体高功率器件的应用,实现了馈电系统的高功率、高效率和高可靠性等性能指标要求。通过机热一体化设计,形成了一种具有良好力学性能和热学性能的固态有源馈电网络系统。项目完成了规定的环境试验考核,并提交5米S-SAR卫星装星应用验证,结果表明:该固态有源馈电网络满足卫星的使用要求。 展开更多
关键词 5米s频段合成孔径雷达卫星 固态有源馈电网络 T/R组件 氮化镓化合物半导体
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A sink moving scheme based on local residual energy of nodes in wireless sensor networks 被引量:4
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作者 谭长庚 许可 +1 位作者 王建新 陈松乔 《Journal of Central South University》 SCIE EI CAS 2009年第2期265-268,共4页
In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving ... In the application of periodic data-gathering in sensor networks,sensor nodes located near the sink have to forward the data received from all other nodes to the sink,which depletes their energy very quickly.A moving scheme for the sink based on local residual energy was proposed.In the scheme,the sink periodically moves to a new location with the highest stay-value defined by the average residual energy and the number of neighbors.The scheme can balance energy consumption and prevent nodes around sink from draining their energy very quickly in the networks.The simulation results show that the scheme can prolong the network lifetime by 26%-65%compared with the earlier schemes where the sink is static or moves randomly. 展开更多
关键词 wireless sensor network network lifetime moving scheme residual energy
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DETERMINING THE STRUCTURES AND PARAMETERS OF RADIAL BASIS FUNCTION NEURAL NETWORKS USING IMPROVED GENETIC ALGORITHMS 被引量:1
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作者 Meiqin Liu Jida Chen 《Journal of Central South University》 SCIE EI CAS 1998年第2期68-73,共6页
The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error t... The method of determining the structures and parameters of radial basis function neural networks(RBFNNs) using improved genetic algorithms is proposed. Akaike′s information criterion (AIC) with generalization error term is used as the best criterion of optimizing the structures and parameters of networks. It is shown from the simulation results that the method not only improves the approximation and generalization capability of RBFNNs ,but also obtain the optimal or suboptimal structures of networks. 展开更多
关键词 RADIAL BAsIs function neural network GENETIC algorithms Akaike′s information CRITERION OVERFITTING
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Repositioning of clinically approved drug Bazi Bushen capsule for treatment of Alzheimer′s disease using network pharma⁃cology approach and in vitro experimental validation 被引量:4
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作者 WANG Tongxing CHEN Meng +3 位作者 HOU Bin LIANG Junqing WEI Cong JIA Zhenhua 《中国药理学与毒理学杂志》 CAS 北大核心 2023年第S01期22-23,共2页
OBJECTIVE To explore the new indications and key mechanism of Bazi Bushen capsule(BZBS)by network pharmacology and in vitro experiment.METHODS The potential tar⁃get profiles of the components of BZBS were pre⁃dicted.S... OBJECTIVE To explore the new indications and key mechanism of Bazi Bushen capsule(BZBS)by network pharmacology and in vitro experiment.METHODS The potential tar⁃get profiles of the components of BZBS were pre⁃dicted.Subsequently,new indications for BZBS were predicted by disease ontology(DO)enrich⁃ment analysis and initially validated by GO and KEGG pathway enrichment analysis.Further⁃more,the therapeutic target of BZBS acting on AD signaling pathway were identified by intersec⁃tion analysis.Two Alzheimer′s disease(AD)cell models,BV-2 and SH-SY5Y,were used to pre⁃liminarily verify the anti-AD efficacy and mecha⁃nism of BZBS in vitro.RESULTS In total,1499 non-repeated ingredients were obtained from 16 herbs in BZBS formula,and 1320 BZBS targets with high confidence were predicted.Disease enrichment results strongly suggested that BZBS formula has the potential to be used in the treat⁃ment of AD.In vitro experiments showed that BZ⁃BS could significantly reduce the release of TNF-αand IL-6 and the expression of COX-2 and PSEN1 in Aβ25-35-induced BV-2 cells.BZBS reduced the apoptosis rate of Aβ25-35 induced SH-SY5Y cells,significantly increased mitochon⁃drial membrane potential,reduced the expres⁃sion of Caspase3 active fragment and PSEN1,and increased the expression of IDE.CONCLU⁃SIONS BZBS formula has a potential use in the treatment of AD,which is achieved through regu⁃lation of ERK1/2,NF-κB signaling pathways,and GSK-3β/β-catenin signaling pathway.Further⁃more,the network pharmacology technology is a feasible drug repurposing strategy to reposition new clinical use of approved TCM and explore the mechanism of action.The study lays a foun⁃dation for the subsequent in-depth study of BZBS in the treatment of AD and provides a basis for its application in the clinical treatment of AD. 展开更多
关键词 Drug repositioning Bazi Bushen capsule network pharmacology Alzheimer′s disease Mechanism of action
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Local adaptive transmit power assignment strategy for wireless sensor networks 被引量:1
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作者 赵学健 庄毅 王进 《Journal of Central South University》 SCIE EI CAS 2012年第7期1909-1920,共12页
A distributed local adaptive transmit power assignment (LA-TPA) strategy was proposed to construct a topology with better performance according to the environment and application scenario and prolong the network lifet... A distributed local adaptive transmit power assignment (LA-TPA) strategy was proposed to construct a topology with better performance according to the environment and application scenario and prolong the network lifetime.It takes the path loss exponent and the energy control coefficient into consideration with the aim to accentuate the minimum covering district of each node more accurately and precisely according to various network application scenarios.Besides,a self-healing scheme that enhances the robustness of the network was provided.It makes the topology tolerate more dead nodes than existing algorithms.Simulation was done under OMNeT++ platform and the results show that the LA-TPA strategy is more effective in constructing a well-performance network topology based on various application scenarios and can prolong the network lifetime significantly. 展开更多
关键词 wireless sensor network topology control transmit power assignment range assignment path loss exponent energycontrol coefficient ROBUsTNEss network lifetime
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Novel Newton’s learning algorithm of neural networks 被引量:2
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作者 Long Ning Zhang Fengli 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第2期450-454,共5页
Newton's learning algorithm of NN is presented and realized. In theory, the convergence rate of learning algorithm of NN based on Newton's method must be faster than BP's and other learning algorithms, because the ... Newton's learning algorithm of NN is presented and realized. In theory, the convergence rate of learning algorithm of NN based on Newton's method must be faster than BP's and other learning algorithms, because the gradient method is linearly convergent while Newton's method has second order convergence rate. The fast computing algorithm of Hesse matrix of the cost function of NN is proposed and it is the theory basis of the improvement of Newton's learning algorithm. Simulation results show that the convergence rate of Newton's learning algorithm is high and apparently faster than the traditional BP method's, and the robustness of Newton's learning algorithm is also better than BP method' s. 展开更多
关键词 Newton's method Hesse matrix fast learning BP method neural network.
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Reliable Fuzzy Control for a Class of Nonlinear Networked Control Systems with Time Delay 被引量:23
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作者 FENG Jian WANG Shen-Quan 《自动化学报》 EI CSCD 北大核心 2012年第7期1091-1099,共9页
关键词 网络控制系统 状态时滞 模糊控制 非线性 LYAPUNOV泛函 线性矩阵不等式 网络诱导时延 执行器故障
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Fault detection for nonlinear networked control systems based on fuzzy observer 被引量:6
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作者 Zhangqing Zhu Xiaocheng Jiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第1期129-136,共8页
Security and reliability must be focused on control sys- tems firstly, and fault detection and diagnosis (FDD) is the main theory and technology. Now, there are many positive results in FDD for linear networked cont... Security and reliability must be focused on control sys- tems firstly, and fault detection and diagnosis (FDD) is the main theory and technology. Now, there are many positive results in FDD for linear networked control systems (LNCSs), but nonlinear networked control systems (NNCSs) are less involved. Based on the T-S fuzzy-modeling theory, NNCSs are modeled and network random time-delays are changed into the unknown bounded uncertain part without changing its structure. Then a fuzzy state observer is designed and an observer-based fault detection approach for an NNCS is presented. The main results are given and the relative theories are proved in detail. Finally, some simulation results are given and demonstrate the proposed method is effective. 展开更多
关键词 nonlinear networked control system (NNCs fault detection T-s fuzzy model state observer time-delay.
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Evidential method to identify influential nodes in complex networks 被引量:7
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作者 Hongming Mo Cai Gao Yong Deng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第2期381-387,共7页
Identifying influential nodes in complex networks is still an open issue. In this paper, a new comprehensive centrality mea- sure is proposed based on the Dempster-Shafer evidence theory. The existing measures of degr... Identifying influential nodes in complex networks is still an open issue. In this paper, a new comprehensive centrality mea- sure is proposed based on the Dempster-Shafer evidence theory. The existing measures of degree centrality, betweenness centra- lity and closeness centrality are taken into consideration in the proposed method. Numerical examples are used to illustrate the effectiveness of the proposed method. 展开更多
关键词 Dempster-shafer evidence theory (D-s theory) belief function complex networks influential nodes evidential centrality comprehensive measure
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Modeling and Stability Analysis for Non-linear Network Control System Based on T-S Fuzzy Model 被引量:2
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作者 ZHANG Hong FANG Huajing 《现代电子技术》 2007年第5期138-141,144,共5页
Based on the T-S fuzzy model,this paper presents a new model of non-linear network control system with stochastic transfer delay.Sufficient criterion is proposed to guarantee globally asymptotically stability of this ... Based on the T-S fuzzy model,this paper presents a new model of non-linear network control system with stochastic transfer delay.Sufficient criterion is proposed to guarantee globally asymptotically stability of this two-levels T-S fuzzy model.Also a T-S fuzzy observer of NCS is designed base on this two-levels T-S fuzzy model.All these results present a new approach for networked control system analysis and design. 展开更多
关键词 模糊模型 非线性系统 时延 网络控制系统 通信技术
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基于优化广义S变换和混合输入神经网络的电能质量扰动识别 被引量:1
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作者 刘海涛 武祥 +3 位作者 张淑清 刘大鹏 刘勇 穆勇 《计量学报》 北大核心 2025年第1期53-61,共9页
利用广义S变换时频矩阵中时间最大幅值曲线和频率最大幅值曲线与电能质量信号幅值和频谱包络线的相关性,提出优化广义S变换的方法对高斯窗函数参数进行自适应选取,充分保留了电能质量扰动的幅值和频率特征。然后提出一种混合输入神经网... 利用广义S变换时频矩阵中时间最大幅值曲线和频率最大幅值曲线与电能质量信号幅值和频谱包络线的相关性,提出优化广义S变换的方法对高斯窗函数参数进行自适应选取,充分保留了电能质量扰动的幅值和频率特征。然后提出一种混合输入神经网络框架,分别对原始时间序列和优化广义S变换得到的时频矩阵进行自动特征提取,最后将2种输入提取到的特征进行组合并利用全连接层来识别扰动类型。通过对包含26种电能质量扰动类型的仿真数据集进行训练和验证,结果表明所述方法对扰动识别准确率为99.77%;然后对2种实际电网扰动信号进行测试,对扰动识别准确率仍然能达到92.5%,高于传统单一输入神经网络。 展开更多
关键词 电学计量 电能质量 扰动识别 s变换 卷积神经网络 混合输入
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Extreme Networks 10 Gbit/s以太网数据中心交换机Summit X650开始供货
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《电信科学》 北大核心 2009年第2期123-124,共2页
Extreme Networks公司宣布,其Summit X650 10Gbit/s以太网固定配置交换机已经开始供货,这是一款专门为提高数据中心和高性能网络而设计的产品.具有令人印象深刻的高性价比。
关键词 networks公司 EXTREME sUMMIT 中心交换机 以太网 供货 10GBIT/s 高性能网络
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Flatness predictive model based on T-S cloud reasoning network implemented by DSP 被引量:4
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作者 ZHANG Xiu-ling GAO Wu-yang +1 位作者 LAI Yong-jin CHENG Yan-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2222-2230,共9页
The accuracy of present flatness predictive method is limited and it just belongs to software simulation. In order to improve it, a novel flatness predictive model via T-S cloud reasoning network implemented by digita... The accuracy of present flatness predictive method is limited and it just belongs to software simulation. In order to improve it, a novel flatness predictive model via T-S cloud reasoning network implemented by digital signal processor(DSP) is proposed. First, the combination of genetic algorithm(GA) and simulated annealing algorithm(SAA) is put forward, called GA-SA algorithm, which can make full use of the global search ability of GA and local search ability of SA. Later, based on T-S cloud reasoning neural network, flatness predictive model is designed in DSP. And it is applied to 900 HC reversible cold rolling mill. Experimental results demonstrate that the flatness predictive model via T-S cloud reasoning network can run on the hardware DSP TMS320 F2812 with high accuracy and robustness by using GA-SA algorithm to optimize the model parameter. 展开更多
关键词 T-s CLOUD reasoning neural network CLOUD MODEL FLATNEss predictive MODEL hardware implementation digital signal PROCEssOR genetic ALGORITHM and simulated annealing ALGORITHM (GA-sA)
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基于RF-EHWSN的能量自适应多跳路由协议
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作者 赵怡帆 任力生 王芳 《现代电子技术》 北大核心 2025年第16期13-18,共6页
针对射频能量收集型无线传感器网络(RF-EHWSN)中传统的LEACH协议在簇头选择阶段未考虑节点的剩余能量和通信距离,导致节点能耗过高,从而缩短网络寿命的问题,以及在稳态阶段传输数据使用单跳传输,导致能量消耗不均衡的问题,提出一种能量... 针对射频能量收集型无线传感器网络(RF-EHWSN)中传统的LEACH协议在簇头选择阶段未考虑节点的剩余能量和通信距离,导致节点能耗过高,从而缩短网络寿命的问题,以及在稳态阶段传输数据使用单跳传输,导致能量消耗不均衡的问题,提出一种能量自适应分簇多跳路由协议。该协议在簇建立阶段引入距离因子和能量因子,优化簇首选择过程;在稳态阶段,采用簇间多跳路由,簇首节点通过代价函数寻找中继路由节点,有效降低了数据传输的能量消耗。与LEACH协议和LEACH-C协议对比得到,所提出的协议网络首次出现节点死亡的时间分别延长了344.44%和105.13%,网络节点全部死亡的时间分别延长了86.44%和23.53%,网络能耗分别降低了约23.53%、22.00%,吞吐量分别提高了212.90%、18.52%。实验结果表明,所提出的协议显著延长了网络寿命,均衡了网络能耗,提高了网络吞吐量。 展开更多
关键词 射频能量收集 无线传感器网络 LEACH协议 分簇协议 簇间多跳路由 网络寿命 能量消耗
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基于改进蜻蜓算法的WSNs分簇路由算法
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作者 杨佳 汤嘉乐 +1 位作者 田朋 冉国政 《计算机工程与设计》 北大核心 2025年第6期1625-1631,共7页
为解决无线传感器网络分簇路由算法中节点能量效率低,数据传输不稳定等问题,提出一种基于改进蜻蜓算法优化K均值聚类的分簇路由算法MIDA-K。引入变异算子和边界控制机制,增强蜻蜓算法的全局寻优能力,使用改进后的蜻蜓算法,实现网络节点... 为解决无线传感器网络分簇路由算法中节点能量效率低,数据传输不稳定等问题,提出一种基于改进蜻蜓算法优化K均值聚类的分簇路由算法MIDA-K。引入变异算子和边界控制机制,增强蜻蜓算法的全局寻优能力,使用改进后的蜻蜓算法,实现网络节点的聚类分簇;簇内节点根据能量、距离和位置因子动态选举簇头,改善簇头的质量;在数据传输阶段利用改进的蜻蜓算法建立簇间路由,综合考虑能量、距离和丢包率选择下一跳数据转发节点,优化传输路径。仿真结果表明,所提算法能够有效提升数据传输可靠性,延长网络寿命。 展开更多
关键词 无线传感器网络 蜻蜓算法 变异算子 边界控制 K均值聚类 网络寿命 数据传输可靠性
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广西S/X波段天气雷达组网拼图分析及其在一次台风过程中的应用
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作者 莫祖斯 刘永亮 +6 位作者 李强 韩宇龙 覃月凤 奉意杰 於莹 何忠洪 黎勋 《热带气象学报》 北大核心 2025年第4期519-530,共12页
为更好地对S/X波段天气雷达组网融合在广西区域的应用能力进行评估,利用雷达观测资料,依次进行基数据解析、Z_(H)-K_(DP)综合法衰减订正、单站雷达网格化及多部雷达组网拼图,最终利用组合反射率、等高平面反射率对广西现有雷达组网覆盖... 为更好地对S/X波段天气雷达组网融合在广西区域的应用能力进行评估,利用雷达观测资料,依次进行基数据解析、Z_(H)-K_(DP)综合法衰减订正、单站雷达网格化及多部雷达组网拼图,最终利用组合反射率、等高平面反射率对广西现有雷达组网覆盖能力在2023年第4号台风“泰利”影响过程进行初步应用分析。结果显示:结合径向廓线对比、网格化对比及多个连续体扫得到的反射率对比分析,经过Z_(H)-K_(DP)综合法订正后的X波段天气雷达反射率在一定范围内具有较高的可靠性;将组网拼图结果应用于台风“泰利”暴雨过程分析,对比S波段和S/X波段天气雷达组网后的0.5 km、0.75 km、1.0 km和2.0 km CAPPI(Constant Altitude Plan Position Indicator)组网反射率因子覆盖区域,结果显示X波段加入雷达组网后,得到了空间结构连续、覆盖更广的资料,有效补充了广西新一代天气雷达的低层盲区、阻挡空缺区等。 展开更多
关键词 X波段天气雷达 s波段天气雷达 衰减订正 雷达组网 反射率因子
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