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高速铁路长大隧道GSM-R网络冗余组网方案分析 被引量:5
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作者 袁廷瑞 熊洁 +1 位作者 路晓彤 焦晓辉 《铁路通信信号工程技术》 2024年第1期36-41,共6页
高速铁路长大隧道需要按照GSM-R冗余组网方案进行覆盖。目前GSM-R网络可采用数字直放站与分布式基站作为数字中继设备,两种设备均有多种组网方案。从故障应对能力、载频利用率、建设成本等多个角度开展分析,对比多种高速铁路隧道内GSM-... 高速铁路长大隧道需要按照GSM-R冗余组网方案进行覆盖。目前GSM-R网络可采用数字直放站与分布式基站作为数字中继设备,两种设备均有多种组网方案。从故障应对能力、载频利用率、建设成本等多个角度开展分析,对比多种高速铁路隧道内GSM-R数字中继设备冗余组网方案,提出各种方案的适用范围和性能优劣。 展开更多
关键词 gsm-r 组网 高速铁路 隧道 无线通信
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CTCS-3线路GSM-R网络运维质量评价体系研究 被引量:1
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作者 蒋笑冰 薛强 薛晚亭 《铁路通信信号工程技术》 2024年第4期45-51,共7页
针对高速铁路GSM-R网络承载行车通信业务的特点,分析CTCS-3线路GSM-R网络运维质量评价思路,提出CTCS-3线路GSM-R网络运维质量评价体系,通过GSM-R网络运行数据进行计算得出评价结果,综合反映出CTCS-3线路GSM-R网络运维质量状况。
关键词 CTCS-3线路 gsm-r网络 质量评价
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面向铁路5G-R和GSM-R系统的SPN承载方案研究与试验
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作者 吴军 胡锴 +4 位作者 李恒友 刘清涛 王芳 李春铎 滕蕾 《中国铁路》 北大核心 2024年第8期9-18,共10页
基于铁路5G-R、GSM-R系统业务场景和全球商用部署的SPN创新承载技术,面向铁路5G-R系统特殊应用,建立小颗粒硬管道业务模型和L3VPN到边缘的分组业务模型,提出采用SPN双平面组网并综合承载现网GSM-R业务的E1CBROver小颗粒硬管道方案。SPN... 基于铁路5G-R、GSM-R系统业务场景和全球商用部署的SPN创新承载技术,面向铁路5G-R系统特殊应用,建立小颗粒硬管道业务模型和L3VPN到边缘的分组业务模型,提出采用SPN双平面组网并综合承载现网GSM-R业务的E1CBROver小颗粒硬管道方案。SPN综合承载方案满足5G-R、GSM-R系统铁路行车控制类业务高可靠、高安全的硬隔离承载需求,以及5G-R系统大带宽视频数据业务灵活调度、智能运维的演进需求。提出的方案已完成基于SPN的5G-R、GSM-R基站和核心网端到端功能及可靠性试验验证,试验结果指标优于标准要求,证明面向铁路5G-R、GSM-R系统的SPN综合承载方案安全可行。 展开更多
关键词 5G-R gsm-r SPN 小颗粒硬管道 承载方案 双平面组网
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西延高铁交叉并线区段GSM-R网络覆盖方案
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作者 马义安 石小勇 《铁路技术创新》 2024年第1期73-81,共9页
西延高铁与既有普速包西铁路、郑西高铁存在交叉并线区段,在2个区段均需进行GSM-R网络覆盖规划。首先根据西延高铁设计标准,确定西延高铁GSM-R无线子系统网络采用单网交织覆盖方式,主要从覆盖方式及电平要求、基站容量计算等方面开展论... 西延高铁与既有普速包西铁路、郑西高铁存在交叉并线区段,在2个区段均需进行GSM-R网络覆盖规划。首先根据西延高铁设计标准,确定西延高铁GSM-R无线子系统网络采用单网交织覆盖方式,主要从覆盖方式及电平要求、基站容量计算等方面开展论证分析;从不同铁路列控等级出发,针对延安站交叉并线区段、郑西高铁交叉并线区段,制定相应的网络覆盖方案;对共小区基站开展实际测试,在设计速度350 km/h条件下,接收机天线输入端射频信号最小可用接收电平满足95%时间地点概率下,最小可用接收电平不小于-92 dBm的要求,可为类似复杂区段的GSM-R网络设计方案提供参考。 展开更多
关键词 西延高铁 gsm-r 网络覆盖 枢纽 交叉并线 高普共站
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Screening biomarkers for spinal cord injury using weighted gene co-expression network analysis and machine learning 被引量:5
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作者 Xiaolu Li Ye Yang +3 位作者 Senming Xu Yuchang Gui Jianmin Chen Jianwen Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2723-2734,共12页
Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is s... Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal co rd injury.They can greatly affect nerve regeneration and functional recovery.However,there is still limited understanding of the peripheral immune inflammato ry response in spinal cord inju ry.In this study.we obtained microRNA expression profiles from the peripheral blood of patients with spinal co rd injury using high-throughput sequencing.We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus(GEO)database(GSE151371).We identified 54 differentially expressed microRNAs and 1656 diffe rentially expressed genes using bioinformatics approaches.Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways,such as neutrophil extracellular trap formation pathway,T cell receptor signaling pathway,and nuclear factor-κB signal pathway,we re abnormally activated or inhibited in spinal cord inju ry patient samples.We applied an integrated strategy that combines weighted gene co-expression network analysis,LASSO logistic regression,and SVM-RFE algorithm and identified three biomarke rs associated with spinal cord injury:ANO10,BST1,and ZFP36L2.We verified the expression levels and diagnostic perfo rmance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve.Quantitative polymerase chain reaction results showed that ANO20 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients.We also constructed a small RNA-mRNA interaction network using Cytoscape.Additionally,we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal co rd injury patients using the CIBERSORT tool.The proportions of naive B cells,plasma cells,monocytes,and neutrophils were increased while the proportions of memory B cells,CD8^(+)T cells,resting natural killer cells,resting dendritic cells,and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects,and ANO10,BST1 and ZFP26L2we re closely related to the proportion of certain immune cell types.The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal co rd inju ry and suggest that ANO10,BST2,and ZFP36L2 are potential biomarkers for spinal cord injury.The study was registe red in the Chinese Clinical Trial Registry(registration No.ChiCTR2200066985,December 12,2022). 展开更多
关键词 bioinformatics analysis BIOMARKER CIBERSORT GEO dataset LASSO miRNA-mRNA network RNA sequencing spinal cord injury SVM-RFE weighted gene co-expression network analysis
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Pluggable multitask diffractive neural networks based on cascaded metasurfaces 被引量:3
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作者 Cong He Dan Zhao +8 位作者 Fei Fan Hongqiang Zhou Xin Li Yao Li Junjie Li Fei Dong Yin-Xiao Miao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第2期23-31,共9页
Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been c... Optical neural networks have significant advantages in terms of power consumption,parallelism,and high computing speed,which has intrigued extensive attention in both academic and engineering communities.It has been considered as one of the powerful tools in promoting the fields of imaging processing and object recognition.However,the existing optical system architecture cannot be reconstructed to the realization of multi-functional artificial intelligence systems simultaneously.To push the development of this issue,we propose the pluggable diffractive neural networks(P-DNN),a general paradigm resorting to the cascaded metasurfaces,which can be applied to recognize various tasks by switching internal plug-ins.As the proof-of-principle,the recognition functions of six types of handwritten digits and six types of fashions are numerical simulated and experimental demonstrated at near-infrared regimes.Encouragingly,the proposed paradigm not only improves the flexibility of the optical neural networks but paves the new route for achieving high-speed,low-power and versatile artificial intelligence systems. 展开更多
关键词 optical neural networks diffractive deep neural networks cascaded metasurfaces
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一种简约化GSM-R网络优化方法及系统的研究与实现 被引量:1
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作者 马平娃 《铁道通信信号》 2024年第2期54-62,共9页
对于非列控区段的普速铁路,由于线路等级不高,通常没有配套建设GSM-R无线信号监测设备,也无法直接照搬高速铁路的网络优化及监测系统。为此提出一种简约化的GSM-R网络优化方法和系统解决方案。利用前端感知终端开展线路侧无线信号采集... 对于非列控区段的普速铁路,由于线路等级不高,通常没有配套建设GSM-R无线信号监测设备,也无法直接照搬高速铁路的网络优化及监测系统。为此提出一种简约化的GSM-R网络优化方法和系统解决方案。利用前端感知终端开展线路侧无线信号采集并进行自动化测试,通过公、专融合的网络形式实现路测数据的一键回传;利用后端服务平台建立智能分析系统模型,实现数据的智能融合分析,初步判断并识别铁路沿线无线信号覆盖薄弱区域、GSM-R服务小区异常等情况,自动生成测试报告和网络优化解决方案,并将相关信息传递给线路侧维护人员,以便其及时、精准地进行现场网络优化工作。采用这种智能化、简约化的网络优化方法,符合提质增效、一体化综合维修的建设思路。 展开更多
关键词 普速铁路 gsm-r网络 网络优化 感知终端 无线信号采集 自动化测试 简约化
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铁路GSM-R系统高速适应性测试及分析
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作者 田园 梁轶群 +3 位作者 蒋韵 高尚勇 李岸宁 李德 《铁道标准设计》 北大核心 2024年第1期185-191,共7页
400 km/h的高速铁路技术储备研发可以推动我国高铁的科技创新。高速条件下的服务质量直接关系着业务性能的优劣,而CSD承载的列控业务和GPRS承载的调度命令信息传送业务均涉及列车的运行控制和运营指挥,会对高速列车的行车安全产生重要... 400 km/h的高速铁路技术储备研发可以推动我国高铁的科技创新。高速条件下的服务质量直接关系着业务性能的优劣,而CSD承载的列控业务和GPRS承载的调度命令信息传送业务均涉及列车的运行控制和运营指挥,会对高速列车的行车安全产生重要影响。目前,我国尚未有针对400 km/h的GSM-R系统服务质量参数的评价标准,为保障业务质量和行车安全,采集了不同速度下铁路GSM-R系统服务质量指标试验数据--最小可用接收电平、列控类电路数据和GPRS数据,通过数据分析和理论分析,对这3类指标的传输特性进行研究,得到铁路GSM-R系统在400 km/h的高速适应性结果。结果表明,对于高速铁路GSM-R系统,最小接收电平目前为-92 dBm,在380 km/h等级时需修改为-81 dBm,在400 km/h等级时需修改为-79 dBm;列控类电路数据和GPRS数据传输特性高速适应性较强,均已满足相关标准要求。研究结果为400 km/h的GSM-R系统关键技术参数的评价标准的制定奠定重要基础,为未来高速铁路下一步提速提供参考。 展开更多
关键词 高速铁路 gsm-r系统 服务质量 CSD GPRS
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Social-ecological perspective on the suicidal behaviour factors of early adolescents in China:a network analysis 被引量:2
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作者 Yuan Li Peiying Li +5 位作者 Mengyuan Yuan Yonghan Li Xueying Zhang Juan Chen Gengfu Wang Puyu Su 《General Psychiatry》 CSCD 2024年第1期143-150,共8页
Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To expl... Background In early adolescence,youth are highly prone to suicidal behaviours.Identifying modifiable risk factors during this critical phase is a priority to inform effective suicide prevention strategies.Aims To explore the risk and protective factors of suicidal behaviours(ie,suicidal ideation,plans and attempts)in early adolescence in China using a social-ecological perspective.Methods Using data from the cross-sectional project‘Healthy and Risky Behaviours Among Middle School Students in Anhui Province,China',stratified random cluster sampling was used to select 5724 middle school students who had completed self-report questionnaires in November 2020.Network analysis was employed to examine the correlates of suicidal ideation,plans and attempts at four levels,namely individual(sex,academic performance,serious physical llness/disability,history of self-harm,depression,impulsivity,sleep problems,resilience),family(family economic status,relationship with mother,relationship with father,family violence,childhood abuse,parental mental illness),school(relationship with teachers,relationship with classmates,school-bullying victimisation and perpetration)and social(social support,satisfaction with society).Results In total,37.9%,19.0%and 5.5%of the students reported suicidal ideation,plans and attempts in the past 6 months,respectively.The estimated network revealed that suicidal ideation,plans and attempts were collectively associated with a history of self-harm,sleep problems,childhood abuse,school bullying and victimisation.Centrality analysis indicated that the most influential nodes in the network were history of self-harm and childhood abuse.Notably,the network also showed unique correlates of suicidal ideation(sex,weight=0.60;impulsivity,weight=0.24;family violence,weight=0.17;relationship with teachers,weight=-0.03;school-bullying perpetration,weight=0.22),suicidal plans(social support,weight=-0.15)and suicidal attempts(relationship with mother,weight=-0.10;parental mental llness,weight=0.61).Conclusions This study identified the correlates of suicidal ideation,plans and attempts,and provided practical implications for suicide prevention for young adolescents in China.Firstly,this study highlighted the importance of joint interventions across multiple departments.Secondly,the common risk factors of suicidal ideation,plans and attempts were elucidated.Thirdly,this study proposed target interventions to address the unique influencing factors of suicidal ideation,plans and attempts. 展开更多
关键词 network ANALYSIS PREVENTION
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Image super‐resolution via dynamic network 被引量:1
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作者 Chunwei Tian Xuanyu Zhang +2 位作者 Qi Zhang Mingming Yang Zhaojie Ju 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期837-849,共13页
Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely exp... Convolutional neural networks depend on deep network architectures to extract accurate information for image super‐resolution.However,obtained information of these con-volutional neural networks cannot completely express predicted high‐quality images for complex scenes.A dynamic network for image super‐resolution(DSRNet)is presented,which contains a residual enhancement block,wide enhancement block,feature refine-ment block and construction block.The residual enhancement block is composed of a residual enhanced architecture to facilitate hierarchical features for image super‐resolution.To enhance robustness of obtained super‐resolution model for complex scenes,a wide enhancement block achieves a dynamic architecture to learn more robust information to enhance applicability of an obtained super‐resolution model for varying scenes.To prevent interference of components in a wide enhancement block,a refine-ment block utilises a stacked architecture to accurately learn obtained features.Also,a residual learning operation is embedded in the refinement block to prevent long‐term dependency problem.Finally,a construction block is responsible for reconstructing high‐quality images.Designed heterogeneous architecture can not only facilitate richer structural information,but also be lightweight,which is suitable for mobile digital devices.Experimental results show that our method is more competitive in terms of performance,recovering time of image super‐resolution and complexity.The code of DSRNet can be obtained at https://github.com/hellloxiaotian/DSRNet. 展开更多
关键词 CNN dynamic network image super‐resolution lightweight network
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Mapping Network-Coordinated Stacked Gated Recurrent Units for Turbulence Prediction 被引量:1
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作者 Zhiming Zhang Shangce Gao +2 位作者 MengChu Zhou Mengtao Yan Shuyang Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1331-1341,共11页
Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes i... Accurately predicting fluid forces acting on the sur-face of a structure is crucial in engineering design.However,this task becomes particularly challenging in turbulent flow,due to the complex and irregular changes in the flow field.In this study,we propose a novel deep learning method,named mapping net-work-coordinated stacked gated recurrent units(MSU),for pre-dicting pressure on a circular cylinder from velocity data.Specifi-cally,our coordinated learning strategy is designed to extract the most critical velocity point for prediction,a process that has not been explored before.In our experiments,MSU extracts one point from a velocity field containing 121 points and utilizes this point to accurately predict 100 pressure points on the cylinder.This method significantly reduces the workload of data measure-ment in practical engineering applications.Our experimental results demonstrate that MSU predictions are highly similar to the real turbulent data in both spatio-temporal and individual aspects.Furthermore,the comparison results show that MSU predicts more precise results,even outperforming models that use all velocity field points.Compared with state-of-the-art methods,MSU has an average improvement of more than 45%in various indicators such as root mean square error(RMSE).Through comprehensive and authoritative physical verification,we estab-lished that MSU’s prediction results closely align with pressure field data obtained in real turbulence fields.This confirmation underscores the considerable potential of MSU for practical applications in real engineering scenarios.The code is available at https://github.com/zhangzm0128/MSU. 展开更多
关键词 Convolutional neural network deep learning recurrent neural network turbulence prediction wind load predic-tion.
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Activation Redistribution Based Hybrid Asymmetric Quantization Method of Neural Networks 被引量:1
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作者 Lu Wei Zhong Ma Chaojie Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期981-1000,共20页
The demand for adopting neural networks in resource-constrained embedded devices is continuously increasing.Quantization is one of the most promising solutions to reduce computational cost and memory storage on embedd... The demand for adopting neural networks in resource-constrained embedded devices is continuously increasing.Quantization is one of the most promising solutions to reduce computational cost and memory storage on embedded devices.In order to reduce the complexity and overhead of deploying neural networks on Integeronly hardware,most current quantization methods use a symmetric quantization mapping strategy to quantize a floating-point neural network into an integer network.However,although symmetric quantization has the advantage of easier implementation,it is sub-optimal for cases where the range could be skewed and not symmetric.This often comes at the cost of lower accuracy.This paper proposed an activation redistribution-based hybrid asymmetric quantizationmethod for neural networks.The proposedmethod takes data distribution into consideration and can resolve the contradiction between the quantization accuracy and the ease of implementation,balance the trade-off between clipping range and quantization resolution,and thus improve the accuracy of the quantized neural network.The experimental results indicate that the accuracy of the proposed method is 2.02%and 5.52%higher than the traditional symmetric quantization method for classification and detection tasks,respectively.The proposed method paves the way for computationally intensive neural network models to be deployed on devices with limited computing resources.Codes will be available on https://github.com/ycjcy/Hybrid-Asymmetric-Quantization. 展开更多
关键词 QUANTIZATION neural network hybrid asymmetric ACCURACY
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The optimal atropine concentration for myopia control in Chinese children: a systematic review and network Metaanalysis 被引量:1
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作者 Xiao-Yan Wang Hong-Wei Deng +7 位作者 Jian Yang Xue-Mei Zhu Feng-Ling Xiang Jing Tu Ming-Xue Huang Yun Wang Jin-Hua Gan Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1128-1137,共10页
AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia... AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia.METHODS:A systematic search was conducted across the Cochrane Library,PubMed,Web of Science,EMBASE,CNKI,CBM,VIP,and Wanfang database,encompassing literature on slowing progression of myopia with varying atropine concentrations from database inception to January 17,2024.Data extraction and quality assessment were performed,and a network Meta-analysis was executed using Stata version 14.0 Software.Results were visually represented through graphs.RESULTS:Fourteen papers comprising 2475 cases were included;five different concentrations of atropine solution were used.The network Meta-analysis,along with the surface under the cumulative ranking curve(SUCRA),showed that 1%atropine(100%)>0.05%atropine(74.9%)>0.025%atropine(51.6%)>0.02%atropine(47.9%)>0.01%atropine(25.6%)>control in refraction change and 1%atropine(98.7%)>0.05%atropine(70.4%)>0.02%atropine(61.4%)>0.025%atropine(42%)>0.01%atropine(27.4%)>control in axial length(AL)change.CONCLUSION:In Chinese children and teenagers,the five various concentrations of atropine can reduce the progression of myopia.Although the network Meta-analysis showed that 1%atropine is the best one for controlling refraction and AL change,there is a high incidence of adverse effects with the use of 1%atropine.Therefore,we suggest that 0.05%atropine is optimal for Chinese children to slow myopia progression. 展开更多
关键词 ATROPINE China children and adolescents MYOPIA network Meta-analysis
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Rao Algorithms-Based Structure Optimization for Heterogeneous Wireless Sensor Networks 被引量:1
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作者 Shereen K.Refaay Samia A.Ali +2 位作者 Moumen T.El-Melegy Louai A.Maghrabi Hamdy H.El-Sayed 《Computers, Materials & Continua》 SCIE EI 2024年第1期873-897,共25页
The structural optimization of wireless sensor networks is a critical issue because it impacts energy consumption and hence the network’s lifetime.Many studies have been conducted for homogeneous networks,but few hav... The structural optimization of wireless sensor networks is a critical issue because it impacts energy consumption and hence the network’s lifetime.Many studies have been conducted for homogeneous networks,but few have been performed for heterogeneouswireless sensor networks.This paper utilizes Rao algorithms to optimize the structure of heterogeneous wireless sensor networks according to node locations and their initial energies.The proposed algorithms lack algorithm-specific parameters and metaphorical connotations.The proposed algorithms examine the search space based on the relations of the population with the best,worst,and randomly assigned solutions.The proposed algorithms can be evaluated using any routing protocol,however,we have chosen the well-known routing protocols in the literature:Low Energy Adaptive Clustering Hierarchy(LEACH),Power-Efficient Gathering in Sensor Information Systems(PEAGSIS),Partitioned-based Energy-efficient LEACH(PE-LEACH),and the Power-Efficient Gathering in Sensor Information Systems Neural Network(PEAGSIS-NN)recent routing protocol.We compare our optimized method with the Jaya,the Particle Swarm Optimization-based Energy Efficient Clustering(PSO-EEC)protocol,and the hybrid Harmony Search Algorithm and PSO(HSA-PSO)algorithms.The efficiencies of our proposed algorithms are evaluated by conducting experiments in terms of the network lifetime(first dead node,half dead nodes,and last dead node),energy consumption,packets to cluster head,and packets to the base station.The experimental results were compared with those obtained using the Jaya optimization algorithm.The proposed algorithms exhibited the best performance.The proposed approach successfully prolongs the network lifetime by 71% for the PEAGSIS protocol,51% for the LEACH protocol,10% for the PE-LEACH protocol,and 73% for the PEGSIS-NN protocol;Moreover,it enhances other criteria such as energy conservation,fitness convergence,packets to cluster head,and packets to the base station. 展开更多
关键词 Wireless sensor networks Rao algorithms OPTIMIZATION LEACH PEAGSIS
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Biodiversity metrics on ecological networks: Demonstrated with animal gastrointestinal microbiomes 被引量:1
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作者 Zhanshan(Sam)Ma Lianwei Li 《Zoological Research(Diversity and Conservation)》 2024年第1期51-65,共15页
Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity... Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity should be similar with measuring national wealth.Indeed,there have been many parallels between ecology and economics,actually beyond analogies.For example,arguably the second most widely used biodiversity metric,Simpson(1949)’s diversity index,is a function of familiar Gini-index in economics.One of the biggest challenges has been the high“diversity”of diversity indexes due to their excessive“speciation”-there are so many indexes,similar to each country’s sovereign currency-leaving confused diversity practitioners in dilemma.In 1973,Hill introduced the concept of“numbers equivalent”,which is based on Renyi entropy and originated in economics,but possibly due to his abstruse interpretation of the concept,his message was not widely received by ecologists until nearly four decades later.What Hill suggested was similar to link the US dollar to gold at the rate of$35 per ounce under the Bretton Woods system.The Hill numbers now are considered most appropriate biodiversity metrics system,unifying Shannon,Simpson and other diversity indexes.Here,we approach to another paradigmatic shift-measuring biodiversity on ecological networks-demonstrated with animal gastrointestinal microbiomes representing four major invertebrate classes and all six vertebrate classes.The network diversity can reveal the diversity of species interactions,which is a necessary step for understanding the spatial and temporal structures and dynamics of biodiversity across environmental gradients. 展开更多
关键词 Biodiversity on network Hill numbers Animal gut microbiome network link diversity network species diversity network abundance-weighted link diversity
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Multi-Scale-Matching neural networks for thin plate bending problem 被引量:1
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作者 Lei Zhang Guowei He 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期11-15,共5页
Physics-informed neural networks are a useful machine learning method for solving differential equations,but encounter challenges in effectively learning thin boundary layers within singular perturbation problems.To r... Physics-informed neural networks are a useful machine learning method for solving differential equations,but encounter challenges in effectively learning thin boundary layers within singular perturbation problems.To resolve this issue,multi-scale-matching neural networks are proposed to solve the singular perturbation problems.Inspired by matched asymptotic expansions,the solution is decomposed into inner solutions for small scales and outer solutions for large scales,corresponding to boundary layers and outer regions,respectively.Moreover,to conform neural networks,we introduce exponential stretched variables in the boundary layers to avoid semiinfinite region problems.Numerical results for the thin plate problem validate the proposed method. 展开更多
关键词 Singular perturbation Physics-informed neural networks Boundary layer Machine learning
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Correcting Climate Model Sea Surface Temperature Simulations with Generative Adversarial Networks:Climatology,Interannual Variability,and Extremes 被引量:2
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作者 Ya WANG Gang HUANG +6 位作者 Baoxiang PAN Pengfei LIN Niklas BOERS Weichen TAO Yutong CHEN BO LIU Haijie LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1299-1312,共14页
Climate models are vital for understanding and projecting global climate change and its associated impacts.However,these models suffer from biases that limit their accuracy in historical simulations and the trustworth... Climate models are vital for understanding and projecting global climate change and its associated impacts.However,these models suffer from biases that limit their accuracy in historical simulations and the trustworthiness of future projections.Addressing these challenges requires addressing internal variability,hindering the direct alignment between model simulations and observations,and thwarting conventional supervised learning methods.Here,we employ an unsupervised Cycle-consistent Generative Adversarial Network(CycleGAN),to correct daily Sea Surface Temperature(SST)simulations from the Community Earth System Model 2(CESM2).Our results reveal that the CycleGAN not only corrects climatological biases but also improves the simulation of major dynamic modes including the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole mode,as well as SST extremes.Notably,it substantially corrects climatological SST biases,decreasing the globally averaged Root-Mean-Square Error(RMSE)by 58%.Intriguingly,the CycleGAN effectively addresses the well-known excessive westward bias in ENSO SST anomalies,a common issue in climate models that traditional methods,like quantile mapping,struggle to rectify.Additionally,it substantially improves the simulation of SST extremes,raising the pattern correlation coefficient(PCC)from 0.56 to 0.88 and lowering the RMSE from 0.5 to 0.32.This enhancement is attributed to better representations of interannual,intraseasonal,and synoptic scales variabilities.Our study offers a novel approach to correct global SST simulations and underscores its effectiveness across different time scales and primary dynamical modes. 展开更多
关键词 generative adversarial networks model bias deep learning El Niño-Southern Oscillation marine heatwaves
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Unraveling the Fundamental Mechanism of Interface Conductive Network Influence on the Fast‑Charging Performance of SiO‑Based Anode for Lithium‑Ion Batteries 被引量:1
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作者 Ruirui Zhang Zhexi Xiao +6 位作者 Zhenkang Lin Xinghao Yan Ziying He Hairong Jiang Zhou Yang Xilai Jia Fei Wei 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期53-68,共16页
Progress in the fast charging of high-capacity silicon monoxide(SiO)-based anode is currently hindered by insufficient conductivity and notable volume expansion.The construction of an interface conductive network effe... Progress in the fast charging of high-capacity silicon monoxide(SiO)-based anode is currently hindered by insufficient conductivity and notable volume expansion.The construction of an interface conductive network effectively addresses the aforementioned problems;however,the impact of its quality on lithium-ion transfer and structure durability is yet to be explored.Herein,the influence of an interface conductive network on ionic transport and mechanical stability under fast charging is explored for the first time.2D modeling simulation and Cryo-transmission electron microscopy precisely reveal the mitigation of interface polarization owing to a higher fraction of conductive inorganic species formation in bilayer solid electrolyte interphase is mainly responsible for a linear decrease in ionic diffusion energy barrier.Furthermore,atomic force microscopy and Raman shift exhibit substantial stress dissipation generated by a complete conductive network,which is critical to the linear reduction of electrode residual stress.This study provides insights into the rational design of optimized interface SiO-based anodes with reinforced fast-charging performance. 展开更多
关键词 Fast charging SiO anode Interface conductive network Ionic transport Mechanical stability
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Multi-scale physics-informed neural networks for solving high Reynolds number boundary layer flows based on matched asymptotic expansions 被引量:1
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作者 Jianlin Huang Rundi Qiu +1 位作者 Jingzhu Wang Yiwei Wang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期76-81,共6页
Multi-scale system remains a classical scientific problem in fluid dynamics,biology,etc.In the present study,a scheme of multi-scale Physics-informed neural networks is proposed to solve the boundary layer flow at hig... Multi-scale system remains a classical scientific problem in fluid dynamics,biology,etc.In the present study,a scheme of multi-scale Physics-informed neural networks is proposed to solve the boundary layer flow at high Reynolds numbers without any data.The flow is divided into several regions with different scales based on Prandtl's boundary theory.Different regions are solved with governing equations in different scales.The method of matched asymptotic expansions is used to make the flow field continuously.A flow on a semi infinite flat plate at a high Reynolds number is considered a multi-scale problem because the boundary layer scale is much smaller than the outer flow scale.The results are compared with the reference numerical solutions,which show that the msPINNs can solve the multi-scale problem of the boundary layer in high Reynolds number flows.This scheme can be developed for more multi-scale problems in the future. 展开更多
关键词 Physics-informed neural networks(PINNs) MULTI-SCALE Fluid dynamics Boundary layer
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Insights into microbiota community dynamics and flavor development mechanism during golden pomfret(Trachinotus ovatus)fermentation based on single-molecule real-time sequencing and molecular networking analysis 被引量:1
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作者 Yueqi Wang Qian Chen +5 位作者 Huan Xiang Dongxiao Sun-Waterhouse Shengjun Chen Yongqiang Zhao Laihao Li Yanyan Wu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期101-114,共14页
Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the ... Popular fermented golden pomfret(Trachinotus ovatus)is prepared via spontaneous fermentation;however,the mechanisms underlying the regulation of its flavor development remain unclear.This study shows the roles of the complex microbiota and the dynamic changes in microbial community and flavor compounds during fish fermentation.Single-molecule real-time sequencing and molecular networking analysis revealed the correlations among different microbial genera and the relationships between microbial taxa and volatile compounds.Mechanisms underlying flavor development were also elucidated via KEGG based functional annotations.Clostridium,Shewanella,and Staphylococcus were the dominant microbial genera.Forty-nine volatile compounds were detected in the fermented fish samples,with thirteen identified as characteristic volatile compounds(ROAV>1).Volatile profiles resulted from the interactions among the microorganisms and derived enzymes,with the main metabolic pathways being amino acid biosynthesis/metabolism,carbon metabolism,and glycolysis/gluconeogenesis.This study demonstrated the approaches for distinguishing key microbiota associated with volatile compounds and monitoring the industrial production of high-quality fermented fish products. 展开更多
关键词 Fermented golden pomfret Microbiota community Volatile compound Co-occurrence network Metabolic pathway
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