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An Efficient Federated Learning Framework Deployed in Resource-Constrained IoV:User Selection and Learning Time Optimization Schemes
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作者 Qiang Wang Shaoyi Xu +1 位作者 Rongtao Xu Dongji Li 《China Communications》 SCIE CSCD 2023年第12期111-130,共20页
In this article,an efficient federated learning(FL)Framework in the Internet of Vehicles(IoV)is studied.In the considered model,vehicle users implement an FL algorithm by training their local FL models and sending the... In this article,an efficient federated learning(FL)Framework in the Internet of Vehicles(IoV)is studied.In the considered model,vehicle users implement an FL algorithm by training their local FL models and sending their models to a base station(BS)that generates a global FL model through the model aggregation.Since each user owns data samples with diverse sizes and different quality,it is necessary for the BS to select the proper participating users to acquire a better global model.Meanwhile,considering the high computational overhead of existing selection methods based on the gradient,the lightweight user selection scheme based on the loss decay is proposed.Due to the limited wireless bandwidth,the BS needs to select an suitable subset of users to implement the FL algorithm.Moreover,the vehicle users’computing resource that can be used for FL training is usually limited in the IoV when other multiple tasks are required to be executed.The local model training and model parameter transmission of FL will have significant effects on the latency of FL.To address this issue,the joint communication and computing optimization problem is formulated whose objective is to minimize the FL delay in the resource-constrained system.To solve the complex nonconvex problem,an algorithm based on the concave-convex procedure(CCCP)is proposed,which can achieve superior performance in the small-scale and delay-insensitive FL system.Due to the fact that the convergence rate of CCCP method is too slow in a large-scale FL system,this method is not suitable for delay-sensitive applications.To solve this issue,a block coordinate descent algorithm based on the one-step projected gradient method is proposed to decrease the complexity of the solution at the cost of light performance degrading.Simulations are conducted and numerical results show the good performance of the proposed methods. 展开更多
关键词 block coordinate descent concave-convex procedure federated learning learning time resource allocation
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Exploring Paths of Students'Academic Burden Reduction in the East Asian Educational Circle:An Analysis of Learning Time Investment and Efficiency Based on PISA 2022
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作者 XU Jinjie LU Jing 《Frontiers of Education in China》 2024年第3期235-250,共16页
By comparing the changes from the Organization for Economic Co-operation and Development's results of Programme for International Student Assessment(PISA)2018 and 2022,it is found that 15-year-old students in East... By comparing the changes from the Organization for Economic Co-operation and Development's results of Programme for International Student Assessment(PISA)2018 and 2022,it is found that 15-year-old students in East Asian countries and economies maintain a commanding lead in reading,mathematics,and science.These students from regions such as Singapore,Japan,the Republic of Korea,Hong Kong(China),Macao(China),and Chinese Taipei not only sustain their academic excellence but also experience improvements in learning efficiency and their sense of belonging at school.Drawing on the PISA 2022 data,this study analyzes students'learning time investment,out-of-school-hours(OsH)services,and their relationship with student academic performance.The results show that the above countries and economies have achieved encouraging results in academic burden reduction by decreasing learning time in regular school lessons,controlling homework time,and providing OsH services.These distinctive policy interventions can serve as valuable reference points for the Chinese Mainland's ongoing implementation of the"double reduction"policy while facilitating an informed judgment of potential risks. 展开更多
关键词 Programme for International Student Assessment(PISA)2022 East Asian educational circle academic burden reduction learning time
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Support vector regression modeling in recursive just-in-time learning framework for adaptive soft sensing of naphtha boiling point in crude distillation unit 被引量:4
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作者 Venkata Vijayan S Hare Krishna Mohanta Ajaya Kumar Pani 《Petroleum Science》 SCIE CAS CSCD 2021年第4期1230-1239,共10页
Prediction of primary quality variables in real time with adaptation capability for varying process conditions is a critical task in process industries.This article focuses on the development of non-linear adaptive so... Prediction of primary quality variables in real time with adaptation capability for varying process conditions is a critical task in process industries.This article focuses on the development of non-linear adaptive soft sensors for prediction of naphtha initial boiling point(IBP)and end boiling point(EBP)in crude distillation unit.In this work,adaptive inferential sensors with linear and non-linear local models are reported based on recursive just in time learning(JITL)approach.The different types of local models designed are locally weighted regression(LWR),multiple linear regression(MLR),partial least squares regression(PLS)and support vector regression(SVR).In addition to model development,the effect of relevant dataset size on model prediction accuracy and model computation time is also investigated.Results show that the JITL model based on support vector regression with iterative single data algorithm optimization(ISDA)local model(JITL-SVR:ISDA)yielded best prediction accuracy in reasonable computation time. 展开更多
关键词 Adaptive soft sensor Just in time learning Regression Support vector regression Naphtha boiling point
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Multimodality Prediction of Chaotic Time Series with Sparse Hard-Cut EM Learning of the Gaussian Process Mixture Model 被引量:1
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作者 周亚同 樊煜 +1 位作者 陈子一 孙建成 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期22-26,共5页
The contribution of this work is twofold: (1) a multimodality prediction method of chaotic time series with the Gaussian process mixture (GPM) model is proposed, which employs a divide and conquer strategy. It au... The contribution of this work is twofold: (1) a multimodality prediction method of chaotic time series with the Gaussian process mixture (GPM) model is proposed, which employs a divide and conquer strategy. It automatically divides the chaotic time series into multiple modalities with different extrinsic patterns and intrinsic characteristics, and thus can more precisely fit the chaotic time series. (2) An effective sparse hard-cut expec- tation maximization (SHC-EM) learning algorithm for the GPM model is proposed to improve the prediction performance. SHO-EM replaces a large learning sample set with fewer pseudo inputs, accelerating model learning based on these pseudo inputs. Experiments on Lorenz and Chua time series demonstrate that the proposed method yields not only accurate multimodality prediction, but also the prediction confidence interval SHC-EM outperforms the traditional variational 1earning in terms of both prediction accuracy and speed. In addition, SHC-EM is more robust and insusceptible to noise than variational learning. 展开更多
关键词 GPM Multimodality Prediction of Chaotic time Series with Sparse Hard-Cut EM learning of the Gaussian Process Mixture Model EM SHC
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The Lightweight Edge-Side Fault Diagnosis Approach Based on Spiking Neural Network
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作者 Jingting Mei Yang Yang +2 位作者 Zhipeng Gao Lanlan Rui Yijing Lin 《Computers, Materials & Continua》 SCIE EI 2024年第6期4883-4904,共22页
Network fault diagnosis methods play a vital role in maintaining network service quality and enhancing user experience as an integral component of intelligent network management.Considering the unique characteristics ... Network fault diagnosis methods play a vital role in maintaining network service quality and enhancing user experience as an integral component of intelligent network management.Considering the unique characteristics of edge networks,such as limited resources,complex network faults,and the need for high real-time performance,enhancing and optimizing existing network fault diagnosis methods is necessary.Therefore,this paper proposes the lightweight edge-side fault diagnosis approach based on a spiking neural network(LSNN).Firstly,we use the Izhikevich neurons model to replace the Leaky Integrate and Fire(LIF)neurons model in the LSNN model.Izhikevich neurons inherit the simplicity of LIF neurons but also possess richer behavioral characteristics and flexibility to handle diverse data inputs.Inspired by Fast Spiking Interneurons(FSIs)with a high-frequency firing pattern,we use the parameters of FSIs.Secondly,inspired by the connection mode based on spiking dynamics in the basal ganglia(BG)area of the brain,we propose the pruning approach based on the FSIs of the BG in LSNN to improve computational efficiency and reduce the demand for computing resources and energy consumption.Furthermore,we propose a multiple iterative Dynamic Spike Timing Dependent Plasticity(DSTDP)algorithm to enhance the accuracy of the LSNN model.Experiments on two server fault datasets demonstrate significant precision,recall,and F1 improvements across three diagnosis dimensions.Simultaneously,lightweight indicators such as Params and FLOPs significantly reduced,showcasing the LSNN’s advanced performance and model efficiency.To conclude,experiment results on a pair of datasets indicate that the LSNN model surpasses traditional models and achieves cutting-edge outcomes in network fault diagnosis tasks. 展开更多
关键词 Network fault diagnosis edge networks Izhikevich neurons PRUNING dynamic spike timing dependent plasticity learning
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Root microbiota shift in rice correlates with resident time in the field and developmental stage 被引量:34
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作者 Jingying Zhang Na Zhang +12 位作者 Yong-Xin Liu Xiaoning Zhang Bin Hu Yuan Qin Haoran Xu Hui Wang Xiaoxuan Guo Jingmei Qian Wei Wang Pengfan Zhang Tao Jin Chengcai Chu Yang Bai 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第6期613-621,共9页
Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota compo... Land plants in natural soil form intimate relationships with the diverse root bacterial microbiota. A growing body of evidence shows that these microbes are important for plant growth and health. Root microbiota composition has been widely studied in several model plants and crops; however, little is known about how root microbiota vary throughout the plant's life cycle under field conditions. We performed longitudinal dense sampling in field trials to track the time-series shift of the root microbiota from two representative rice cultivars in two separate locations in China. We found that the rice root microbiota varied dramatically during the vegetative stages and stabilized from the beginning of the reproductive stage, after which the root microbiota underwent relatively minor changes until rice ripening. Notably, both rice genotype and geographical location influenced the patterns of root microbiota shift that occurred during plant growth. The relative abundance of Deltaproteobacteria in roots significantly increased overtime throughout the entire life cycle of rice, while that of Betaproteobacteria, Firmicutes, and Gammaproteobacteria decreased. By a machine learning approach, we identified biomarker taxa and established a model to correlate root microbiota with rice resident time in the field(e.g., Nitrospira accumulated from 5 weeks/tillering in field-grown rice). Our work provides insights into the process of rice root microbiota establishment. 展开更多
关键词 rice root microbiota time-series shift biomarker taxa residence time in the field developmental stages modeling machine learning
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Adaptive level of autonomy for human-UAVs collaborative surveillance using situated fuzzy cognitive maps 被引量:10
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作者 Zhe ZHAO Yifeng NIU Lincheng SHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第11期2835-2850,共16页
Collaborating with a squad of Unmanned Aerial Vehicles(UAVs)is challenging for a human operator in a cooperative surveillance task.In this paper,we propose a cognitive model that can dynamically adjust the Levels of A... Collaborating with a squad of Unmanned Aerial Vehicles(UAVs)is challenging for a human operator in a cooperative surveillance task.In this paper,we propose a cognitive model that can dynamically adjust the Levels of Autonomy(LOA)of the human-UAVs team according to the changes in task complexity and human cognitive states.Specifically,we use the Situated Fuzzy Cognitive Map(Si FCM)to model the relations among tasks,situations,human states and LOA.A recurrent structure has been used to learn the strategy of adjusting the LOA,while the collaboration task is separated into a perception routine and a control routine.Experiment results have shown that the workload of the human operator is well balanced with the task efficiency. 展开更多
关键词 Adaptive LOA Cognitive Model Human-UAVs collaboration Situated Fuzzy Cognitive Map(SiFCM) time series learning
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