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Time Predictable Modeling Method for GPU Architecture with SIMT and Cache Miss Awareness
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作者 Shaojie Zhang 《Journal of Electronic Research and Application》 2024年第2期109-115,共7页
Graphics Processing Units(GPUs)are used to accelerate computing-intensive tasks,such as neural networks,data analysis,high-performance computing,etc.In the past decade or so,researchers have done a lot of work on GPU ... Graphics Processing Units(GPUs)are used to accelerate computing-intensive tasks,such as neural networks,data analysis,high-performance computing,etc.In the past decade or so,researchers have done a lot of work on GPU architecture and proposed a variety of theories and methods to study the microarchitectural characteristics of various GPUs.In this study,the GPU serves as a co-processor and works together with the CPU in an embedded real-time system to handle computationally intensive tasks.It models the architecture of the GPU and further considers it based on some excellent work.The SIMT mechanism and Cache-miss situation provide a more detailed analysis of the GPU architecture.In order to verify the GPU architecture model proposed in this article,10 GPU kernel_task and an Nvidia GPU device were used to perform experiments.The experimental results showed that the minimum error between the kernel task execution time predicted by the GPU architecture model proposed in this article and the actual measured kernel task execution time was 3.80%,and the maximum error was 8.30%. 展开更多
关键词 Heterogeneous computing GPU Architecture modeling time predictability
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Travel time prediction model of freeway based on gradient boosting decision tree 被引量:7
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作者 Cheng Juan Chen Xianhua 《Journal of Southeast University(English Edition)》 EI CAS 2019年第3期393-398,共6页
To investigate the travel time prediction method of the freeway, a model based on the gradient boosting decision tree (GBDT) is proposed. Eleven variables (namely, travel time in current period T i , traffic flow in c... To investigate the travel time prediction method of the freeway, a model based on the gradient boosting decision tree (GBDT) is proposed. Eleven variables (namely, travel time in current period T i , traffic flow in current period Q i , speed in current period V i , density in current period K i , the number of vehicles in current period N i , occupancy in current period R i , traffic state parameter in current period X i , travel time in previous time period T i -1 , etc.) are selected to predict the travel time for 10 min ahead in the proposed model. Data obtained from VISSIM simulation is used to train and test the model. The results demonstrate that the prediction error of the GBDT model is smaller than those of the back propagation (BP) neural network model and the support vector machine (SVM) model. Travel time in current period T i is the most important variable among all variables in the GBDT model. The GBDT model can produce more accurate prediction results and mine the hidden nonlinear relationships deeply between variables and the predicted travel time. 展开更多
关键词 gradient boosting decision tree (GBDT) travel time prediction FREEWAY traffic state parameter
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Bus Arrival Time Prediction Based on Mixed Model 被引量:4
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作者 Jinglin Li Jie Gao +1 位作者 Yu Yang Heran Wei 《China Communications》 SCIE CSCD 2017年第5期38-47,共10页
How to predict the bus arrival time accurately is a crucial problem to be solved in Internet of Vehicle. Existed methods cannot solve the problem effectively for ignoring the traffic delay jitter. In this paper,a thre... How to predict the bus arrival time accurately is a crucial problem to be solved in Internet of Vehicle. Existed methods cannot solve the problem effectively for ignoring the traffic delay jitter. In this paper,a three-stage mixed model is proposed for bus arrival time prediction. The first stage is pattern training. In this stage,the traffic delay jitter patterns(TDJP)are mined by K nearest neighbor and K-means in the historical traffic time data. The second stage is the single-step prediction,which is based on real-time adjusted Kalman filter with a modification of historical TDJP. In the third stage,as the influence of historical law is increasing in long distance prediction,we combine the single-step prediction dynamically with Markov historical transfer model to conduct the multi-step prediction. The experimental results show that the proposed single-step prediction model performs better in accuracy and efficiency than short-term traffic flow prediction and dynamic Kalman filter. The multi-step prediction provides a higher level veracity and reliability in travel time forecasting than short-term traffic flow and historical traffic pattern prediction models. 展开更多
关键词 bus arrival time prediction traffic delay jitter pattern internet of vehicle
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A PSO-SVM Model for Short-Term Travel Time Prediction Based on Bluetooth Technology 被引量:3
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作者 Qun Wang Zhuyun Liu Zhongren Peng 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期7-14,共8页
The accurate prediction of travel time along roadway provides valuable traffic information for travelers and traffic managers. Aiming at short-term travel time forecasting on urban arterials,a prediction model( PSOSVM... The accurate prediction of travel time along roadway provides valuable traffic information for travelers and traffic managers. Aiming at short-term travel time forecasting on urban arterials,a prediction model( PSOSVM) combining support vector machine( SVM) and particle swarm optimization( PSO) is developed. Travel time data collected with Bluetooth devices are used to calibrate the proposed model. Field experiments show that the PSO-SVM model 's error indicators are lower than the single SVM model and the BP neural network( BPNN) model. Particularly,the mean-absolute percentage error( MAPE) of PSO-SVM is only 9. 453 4 %which is less than that of the single SVM model( 12. 230 2 %) and the BPNN model( 15. 314 7 %). The results indicate that the proposed PSO-SVM model is feasible and more effective than other models for shortterm travel time prediction on urban arterials. 展开更多
关键词 urban arterials travel time prediction Bluetooth detection support vector machine(SVM) particle swarm optimization(PSO)
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Ship motion extreme short time prediction of ship pitch based on diagonal recurrent neural network 被引量:3
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作者 SHEN Yan XIE Mei-ping 《Journal of Marine Science and Application》 2005年第2期56-60,共5页
A DRNN (diagonal recurrent neural network) and its RPE (recurrent prediction error) learning algorithm are proposed in this paper .Using of the simple structure of DRNN can reduce the capacity of calculation. The prin... A DRNN (diagonal recurrent neural network) and its RPE (recurrent prediction error) learning algorithm are proposed in this paper .Using of the simple structure of DRNN can reduce the capacity of calculation. The principle of RPE learning algorithm is to adjust weights along the direction of Gauss-Newton. Meanwhile, it is unnecessary to calculate the second local derivative and the inverse matrixes, whose unbiasedness is proved. With application to the extremely short time prediction of large ship pitch, satisfactory results are obtained. Prediction effect of this algorithm is compared with that of auto-regression and periodical diagram method, and comparison results show that the proposed algorithm is feasible. 展开更多
关键词 extreme short time prediction diagonal recursive neural network recurrent prediction error learning algorithm UNBIASEDNESS
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Route Temporal⁃Spatial Information Based Residual Neural Networks for Bus Arrival Time Prediction 被引量:1
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作者 Chao Yang Xiaolei Ru Bin Hu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第4期31-39,共9页
Bus arrival time prediction contributes to the quality improvement of public transport services.Passengers can arrange departure time effectively if they know the accurate bus arrival time in advance.We proposed a mac... Bus arrival time prediction contributes to the quality improvement of public transport services.Passengers can arrange departure time effectively if they know the accurate bus arrival time in advance.We proposed a machine⁃learning approach,RTSI⁃ResNet,to forecast the bus arrival time at target stations.The residual neural network framework was employed to model the bus route temporal⁃spatial information.It was found that the bus travel time on a segment between two stations not only had correlation with the preceding buses,but also had common change trends with nearby downstream/upstream segments.Two features about bus travel time and headway were extracted from bus route including target section in both forward and reverse directions to constitute the route temporal⁃spatial information,which reflects the road traffic conditions comprehensively.Experiments on the bus trajectory data of route No.10 in Shenzhen public transport system demonstrated that the proposed RTSI⁃ResNet outperformed other well⁃known methods(e.g.,RNN/LSTM,SVM).Specifically,the advantage was more significant when the distance between bus and the target station was farther. 展开更多
关键词 bus arrival time prediction route temporal⁃spatial information residual neural network recurrent neural network bus trajectory data
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Remaining Time Prediction for Business Processes with Concurrency Based on Log Representation
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作者 Rui Cao Weijian Ni +3 位作者 Qingtian Zeng Faming Lu Cong Liu Hua Duan 《China Communications》 SCIE CSCD 2021年第11期76-91,共16页
Remaining time prediction of business processes plays an important role in resource scheduling and plan making.The structural features of single process instance and the concurrent running of multiple process instance... Remaining time prediction of business processes plays an important role in resource scheduling and plan making.The structural features of single process instance and the concurrent running of multiple process instances are the main factors that affect the accuracy of the remaining time prediction.Existing prediction methods does not take full advantage of these two aspects into consideration.To address this issue,a new prediction method based on trace representation is proposed.More specifically,we first associate the prefix set generated by the event log to different states of the transition system,and encode the structural features of the prefixes in the state.Then,an annotation containing the feature representation for the prefix and the corresponding remaining time are added to each state to obtain an extended transition system.Next,states in the extended transition system are partitioned by the different lengths of the states,which considers concurrency among multiple process instances.Finally,the long short-term memory(LSTM)deep recurrent neural networks are applied to each partition for predicting the remaining time of new running instances.By extensive experimental evaluation using synthetic event logs and reallife event logs,we show that the proposed method outperforms existing baseline methods. 展开更多
关键词 business process monitoring remaining time prediction LSTM feature representation CONCURRENCY
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Multiple Extreme Learning Machines Based Arrival Time Prediction for Public Bus Transport
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作者 J.Jalaney R.S.Ganesh 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2819-2834,共16页
Due to fast-growing urbanization,the traffic management system becomes a crucial problem owing to the rapid growth in the number of vehicles The research proposes an Intelligent public transportation system where info... Due to fast-growing urbanization,the traffic management system becomes a crucial problem owing to the rapid growth in the number of vehicles The research proposes an Intelligent public transportation system where informa-tion regarding all the buses connecting in a city will be gathered,processed and accurate bus arrival time prediction will be presented to the user.Various linear and time-varying parameters such as distance,waiting time at stops,red signal duration at a traffic signal,traffic density,turning density,rush hours,weather conditions,number of passengers on the bus,type of day,road type,average vehi-cle speed limit,current vehicle speed affecting traffic are used for the analysis.The proposed model exploits the feasibility and applicability of ELM in the travel time forecasting area.Multiple ELMs(MELM)for explicitly training dynamic,road and trajectory information are used in the proposed approach.A large-scale dataset(historical data)obtained from Kerala State Road Transport Corporation is used for training.Simulations are carried out by using MATLAB R2021a.The experiments revealed that the efficiency of MELM is independent of the time of day and day of the week.It can manage huge volumes of data with less human intervention at greater learning speeds.It is found MELM yields prediction with accuracy in the range of 96.7%to 99.08%.The MAE value is between 0.28 to 1.74 minutes with the proposed approach.The study revealed that there could be regularity in bus usage and daily bus rides are predictable with a better degree of accuracy.The research has proved that MELM is superior for arrival time pre-dictions in terms of accuracy and error,compared with other approaches. 展开更多
关键词 Arrival time prediction public transportation extreme learning machine traffic density
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Time Prediction Model of Personalized Affective Support Based on the Programming Process
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作者 Hongyan Xu Tao Lin +2 位作者 Yu Chen Jian Wang Doudou Feng 《计算机教育》 2020年第12期114-121,共8页
In online programming education,if teachers can determine any difficulties their students are experiencing and provide support,it would significantly improve the outcome of their teaching.This paper describes an attem... In online programming education,if teachers can determine any difficulties their students are experiencing and provide support,it would significantly improve the outcome of their teaching.This paper describes an attempt to build a time prediction model on the demand for personalized affective support based on a modified version of the Synthetic Minority Over-sampling Technique.We designed and conducted a data collection experiment based on the specific features of the affective support.Meanwhile,the modified oversampling algorithm can ascertain the time for providing such support for learners,which solves the problem of a class imbalance distribution.In addition,we obtained a sorting algorithm of the time prediction regarding the demand for personalized affective support in programming learning and constructed a time prediction model on the demand for affective support.Meanwhile,we conducted experiments on both public data and our own collected data to verify the effectiveness of the constructed model.The results show that the model is able to judge whether learners need affective support during the writing code process. 展开更多
关键词 time prediction Programming learning Affective support PERSONALIZED
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The Time Prediction of Ice Meltdown on An Aerial Conductor
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作者 Heyun Liu (Department of Power Engineering Changsha University of Electric Power) Suyi Huang (Department of Power Engineering Huazhong University of Science and Technology) 《Electricity》 2000年第1期52-54,共3页
This paper analyses the melting process of an ice layer formed on an aerial conductor. It is found that the melting process consists of two distinct phases: the ice surrounding the conductor (the first regime) and the... This paper analyses the melting process of an ice layer formed on an aerial conductor. It is found that the melting process consists of two distinct phases: the ice surrounding the conductor (the first regime) and the conductor cutting through the top of the ice shell (the second regime). The formula obtained in this paper to predict the melting time is different from those commonly used. 展开更多
关键词 HEAT Ti The time prediction of Ice Meltdown on An Aerial Conductor
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The Two-dimensional Time Coordinate System and Time Prediction Research of M≥6.7 Strong Earthquakes in the Sichuan-Yunnan Region
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作者 Sun Zongqiang Xie Xiaojing +6 位作者 Gao Huayan Wang Yongmei Fang Yanxun Wang Bin Yao Yuxia Cao Xiaoli Wu Yanfang 《Earthquake Research in China》 CSCD 2015年第1期128-135,共8页
Since the 20 thcentury,the time intervals of M ≥6.7 strong earthquakes in the SichuanYunnan region show obvious regularity.Using the years of the strong events,a twodimensional time coordinate system is generated,bas... Since the 20 thcentury,the time intervals of M ≥6.7 strong earthquakes in the SichuanYunnan region show obvious regularity.Using the years of the strong events,a twodimensional time coordinate system is generated,based on which,the time prediction model is constructed for strong earthquakes in the Sichuan-Yunnan region.Prediction analysis shows that there is risk of generating four earthquakes with M ≥ 6.7 in the Sichuan-Yunnan region in the future 16 years,and there are strong signals for M ≥6.7earthquakes for periods 2012-2021 and 2025-2029.The strong earthquakes may occur around 2014-2015,2019 and 2027. 展开更多
关键词 The Sichuan-Yunnan region Strong earthquake Two-dimensional timecoordinate system Earthquake prediction time prediction model
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RHMX:Bus Arrival Time Prediction via Mixed Model
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作者 Fei Jia Huibing Zhang Xiaoli Hu 《Journal of Electronic Research and Application》 2021年第6期30-43,共14页
With the widespread use of information technologies such as IoT and big data in the transportation business,traditional passenger transportation has begun to transition and upgrade into intelligent transportation,prov... With the widespread use of information technologies such as IoT and big data in the transportation business,traditional passenger transportation has begun to transition and upgrade into intelligent transportation,providing passengers with a better riding experience.Giving precise bus arrival times is a critical link in achieving urban intelligent transportation.As a result,a mixed model-based bus arrival time prediction model(RHMX)was suggested in this work,which could dynamically forecast bus arrival time based on the input data.First,two sub-models were created:bus station stopping time prediction and interstation running time prediction.The former predicted the stopping time of a running bus at each downstream station in an iterative manner,while the latter projected its running time on each downstream road segment(stations as the break points).Using the two models,a group of time series data on interstation running time and bus station stopping time may be predicted.Following that,the time series data from the two sub-models was fused using long short-term memory(LSTM)to generate an approximate bus arrival time.Finally,using Kalman filtering,the LSTM prediction results were dynamically updated in order to eliminate the influence of aberrant data on the anticipated value and obtain a more precise bus arrival time.The experimental findings showed that the suggested model's accuracy and stability were both improved by 35%and 17%,respectively,over AutoNavi and Baidu. 展开更多
关键词 IOT Big data Bus arrival time prediction Long short-term memory Kalman filtering
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Continuous-Time Prediction of Industrial Paste Thickener System With Differential ODE-Net 被引量:2
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作者 Zhaolin Yuan Xiaorui Li +4 位作者 Di Wu Xiaojuan Ban Nai-Qi Wu Hong-Ning Dai Hao Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第4期686-698,共13页
It is crucial to predict the outputs of a thickening system,including the underflow concentration(UC)and mud pressure,for optimal control of the process.The proliferation of industrial sensors and the availability of ... It is crucial to predict the outputs of a thickening system,including the underflow concentration(UC)and mud pressure,for optimal control of the process.The proliferation of industrial sensors and the availability of thickening-system data make this possible.However,the unique properties of thickening systems,such as the non-linearities,long-time delays,partially observed data,and continuous time evolution pose challenges on building data-driven predictive models.To address the above challenges,we establish an integrated,deep-learning,continuous time network structure that consists of a sequential encoder,a state decoder,and a derivative module to learn the deterministic state space model from thickening systems.Using a case study,we examine our methods with a tailing thickener manufactured by the FLSmidth installed with massive sensors and obtain extensive experimental results.The results demonstrate that the proposed continuous-time model with the sequential encoder achieves better prediction performances than the existing discrete-time models and reduces the negative effects from long time delays by extracting features from historical system trajectories.The proposed method also demonstrates outstanding performances for both short and long term prediction tasks with the two proposed derivative types. 展开更多
关键词 Industrial 24 paste thickener ordinary differential equation(ODE)-net recurrent neural network time series prediction
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Support Vector Regression for Bus Travel Time Prediction Using Wavelet Transform 被引量:2
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作者 Yang Liu Yanjie Ji +1 位作者 Keyu Chen Xinyi Qi 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第3期26-34,共9页
In order to accurately predict bus travel time, a hybrid model based on combining wavelet transform technique with support vector regression(WT-SVR) model is employed. In this model, wavelet decomposition is used to e... In order to accurately predict bus travel time, a hybrid model based on combining wavelet transform technique with support vector regression(WT-SVR) model is employed. In this model, wavelet decomposition is used to extract important information of data at different levels and enhances the forecasting ability of the model. After wavelet transform different components are forecasted by their corresponding SVR predictors. The final prediction result is obtained by the summation of the predicted results for each component. The proposed hybrid model is examined by the data of bus route No.550 in Nanjing, China. The performance of WT-SVR model is evaluated by mean absolute error(MAE), mean absolute percent error(MAPE) and relative mean square error(RMSE), and also compared to regular SVR and ANN models. The results show that the prediction method based on wavelet transform and SVR has better tracking ability and dynamic behavior than regular SVR and ANN models. The forecasting performance is remarkably improved to obtain within 6% MAPE for testing section Ⅰ and 8% MAPE for testing section Ⅱ, which proves that the suggested approach is feasible and applicable in bus travel time prediction. 展开更多
关键词 intelligent TRANSPORTATION BUS TRAVEL time prediction WAVELET TRANSFORM support vector regression hybrid model
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Processing Time Prediction Method Based on SVR in Semiconductor Manufacturing 被引量:1
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作者 朱雪初 乔非 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期98-101,共4页
The prediction problem of the actual value of the dynamic parameters in the simulation model in semiconductor manufacturing was discussed. Considering the fact that the default value of processing time of one certain ... The prediction problem of the actual value of the dynamic parameters in the simulation model in semiconductor manufacturing was discussed. Considering the fact that the default value of processing time of one certain equipment in the simulation model was not the same as its actual value,a general data driven prediction model of the processing time was built based on support vector regression( SVR),with the utilization of manufacturing information in manufacturing execution system( MES). The processing time of one certain equipment was highly related to the status of the equipment itself and the wafers being processed. To uncover the relationship of the processing time with the information of historical products,process flow,technical standard of silicon wafers and manual intervention,data were extracted from MES and used to build a prediction model. This model was employed on an ion implantation equipment as a case, and the effectiveness of the proposed method was shown by comparing with other approaches. 展开更多
关键词 SEMICONDUCTOR MANUFACTURING SUPPORT VECTOR regression(SVR) PROCESSING time prediction
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Deep Learning for Financial Time Series Prediction:A State-of-the-Art Review of Standalone and HybridModels
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作者 Weisi Chen Walayat Hussain +1 位作者 Francesco Cauteruccio Xu Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期187-224,共38页
Financial time series prediction,whether for classification or regression,has been a heated research topic over the last decade.While traditional machine learning algorithms have experienced mediocre results,deep lear... Financial time series prediction,whether for classification or regression,has been a heated research topic over the last decade.While traditional machine learning algorithms have experienced mediocre results,deep learning has largely contributed to the elevation of the prediction performance.Currently,the most up-to-date review of advanced machine learning techniques for financial time series prediction is still lacking,making it challenging for finance domain experts and relevant practitioners to determine which model potentially performs better,what techniques and components are involved,and how themodel can be designed and implemented.This review article provides an overview of techniques,components and frameworks for financial time series prediction,with an emphasis on state-of-the-art deep learning models in the literature from2015 to 2023,including standalonemodels like convolutional neural networks(CNN)that are capable of extracting spatial dependencies within data,and long short-term memory(LSTM)that is designed for handling temporal dependencies;and hybrid models integrating CNN,LSTM,attention mechanism(AM)and other techniques.For illustration and comparison purposes,models proposed in recent studies are mapped to relevant elements of a generalized framework comprised of input,output,feature extraction,prediction,and related processes.Among the state-of-the-artmodels,hybrid models like CNNLSTMand CNN-LSTM-AM in general have been reported superior in performance to stand-alone models like the CNN-only model.Some remaining challenges have been discussed,including non-friendliness for finance domain experts,delayed prediction,domain knowledge negligence,lack of standards,and inability of real-time and highfrequency predictions.The principal contributions of this paper are to provide a one-stop guide for both academia and industry to review,compare and summarize technologies and recent advances in this area,to facilitate smooth and informed implementation,and to highlight future research directions. 展开更多
关键词 Financial time series prediction convolutional neural network long short-term memory deep learning attention mechanism FINANCE
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AFSTGCN:Prediction for multivariate time series using an adaptive fused spatial-temporal graph convolutional network
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作者 Yuteng Xiao Kaijian Xia +5 位作者 Hongsheng Yin Yu-Dong Zhang Zhenjiang Qian Zhaoyang Liu Yuehan Liang Xiaodan Li 《Digital Communications and Networks》 SCIE CSCD 2024年第2期292-303,共12页
The prediction for Multivariate Time Series(MTS)explores the interrelationships among variables at historical moments,extracts their relevant characteristics,and is widely used in finance,weather,complex industries an... The prediction for Multivariate Time Series(MTS)explores the interrelationships among variables at historical moments,extracts their relevant characteristics,and is widely used in finance,weather,complex industries and other fields.Furthermore,it is important to construct a digital twin system.However,existing methods do not take full advantage of the potential properties of variables,which results in poor predicted accuracy.In this paper,we propose the Adaptive Fused Spatial-Temporal Graph Convolutional Network(AFSTGCN).First,to address the problem of the unknown spatial-temporal structure,we construct the Adaptive Fused Spatial-Temporal Graph(AFSTG)layer.Specifically,we fuse the spatial-temporal graph based on the interrelationship of spatial graphs.Simultaneously,we construct the adaptive adjacency matrix of the spatial-temporal graph using node embedding methods.Subsequently,to overcome the insufficient extraction of disordered correlation features,we construct the Adaptive Fused Spatial-Temporal Graph Convolutional(AFSTGC)module.The module forces the reordering of disordered temporal,spatial and spatial-temporal dependencies into rule-like data.AFSTGCN dynamically and synchronously acquires potential temporal,spatial and spatial-temporal correlations,thereby fully extracting rich hierarchical feature information to enhance the predicted accuracy.Experiments on different types of MTS datasets demonstrate that the model achieves state-of-the-art single-step and multi-step performance compared with eight other deep learning models. 展开更多
关键词 Adaptive adjacency matrix Digital twin Graph convolutional network Multivariate time series prediction Spatial-temporal graph
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Numerical Prediction Methods for Clock Deviation Based on Two-Way Satellite Time and Frequency Transfer Data 被引量:3
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作者 GUO Hairong YANG Yuanxi HE Haibo 《Geo-Spatial Information Science》 2008年第2期143-147,共5页
Three functional models, polynomial, spectral analysis, and modified AR model, are studied and compared in fitting and predicting clock deviation based on the data sequence derived from two-way satellite time and freq... Three functional models, polynomial, spectral analysis, and modified AR model, are studied and compared in fitting and predicting clock deviation based on the data sequence derived from two-way satellite time and frequency transfer. A robust equivalent weight is applied, which controls the significant influence of outlying observations. Some conclusions show that the prediction precision of robust estimation is better than that of LS. The prediction precision calculated from smoothed observations is higher than that calculated from sampling observations. As a count of the obvious period variations in the clock deviation sequence, the predicted values of polynomial model are implausible. The prediction precision of spectral analysis model is very low, but the principal periods can be determined. The prediction RMS of 6-hour extrapolation interval is Ins or so, when modified AR model is used. 展开更多
关键词 time prediction time transfer two-way satellite time and frequency transfer
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Highway icing time prediction with deep learning approaches based on data from road sensors 被引量:1
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作者 WANG ShiHong WANG TianLe +4 位作者 PEI Xuan WANG Hao ZHU Qiang TANG Tao HOU TaoGang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2023年第7期1987-1999,共13页
In harsh climates,highway icing poses a hazard to traffic safety and increases road maintenance costs.It is of great significance to predict when the highway icing may occur and take a preventive plan.However,there ar... In harsh climates,highway icing poses a hazard to traffic safety and increases road maintenance costs.It is of great significance to predict when the highway icing may occur and take a preventive plan.However,there are few studies on highway icing time prediction due to the scarcity and complexity of data.In this study,variables of icing temperature,friction,ice percentage,road surface temperature,water film height,saline concentration,and road condition were collected by road sensors distributed on a highway in China.A large-scale time series highway surface information dataset called HighwayIce is formed.Furthermore,a deep learning approach called IceAlarm,composed of long short-term memory neural network(LSTM),multilayer perceptron(MLP),and residual connection,has been developed to predict when the highway will ice.The LSTM is used to process dynamic variables,the MLP is used to process static variables,and the fully-connected layers with residual connections are used to make a deep fusion.The experimental results show that the average mean absolute error before icing using the IceAlarm model is about 6min and outperforms all baseline models.The HighwayIce dataset and IceAlarm model can help improve the prediction accuracy and efficiency of forecasting real-world road icing time,therefore reducing the impact of icy road conditions on traffic. 展开更多
关键词 road icing time prediction road surface condition multilayer perceptron(MLP) long short-term memory(LSTM) residual connection
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The Time and Cost Prediction of Tunnel Boring Machine in Tunnelling
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作者 WU Shijing QIAN Bo GONG Zhibo 《Wuhan University Journal of Natural Sciences》 CAS 2006年第2期385-388,共4页
Making use of microsoft visual studio. net platform, the assistant decision-making system of tunnel boring machine in tunnelling has been built to predict the time and cost. Computation methods of the performance para... Making use of microsoft visual studio. net platform, the assistant decision-making system of tunnel boring machine in tunnelling has been built to predict the time and cost. Computation methods of the performance parameters have been discussed. New time and cost prediction models have been depicted. The multivariate linear regression has been used to make the parameters more precise, which are the key factor to affect the prediction near to the reality. 展开更多
关键词 tunnel boring machine time prediction costprediction assistant decision-making multivariate linear regression
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