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序列网与度量空间的序列商映象──献给高国士教授80寿辰 被引量:9
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作者 林寿 《数学学报(中文版)》 SCIE CSCD 北大核心 1999年第1期49-54,共6页
本文定义了序列网的概念,建立了它与序列拟基、cs网之间的关系,获得了度量空间的确定商映象的一些新刻画.
关键词 序列空间 序列网 序列拟基 序列商映象 度量空间
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序列邻域网与1-序列覆盖映射 被引量:1
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作者 唐古生 《广西大学学报(自然科学版)》 CAS CSCD 2000年第4期286-288,共3页
本文刻划了度量空间 ,局部可分度量空间在一些序列覆盖下象空间的特性。给出了度量空间的 1序列覆盖 msss 像 ,2序列覆盖 msss 像的内在刻划。证明了局部可分度量的 1序列覆盖 ss 像 ,2序列覆盖 ss像的两个等价命题 .
关键词 序列邻域 1-序列(2-序列)覆盖ss-映射 可分层强s-映射 局部可分 拓扑空间
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关于σ点有限序列邻域网 被引量:2
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作者 燕鹏飞 《淮北煤师院学报(自然科学版)》 1999年第2期17-19,共3页
本文证明了具有σ点有限序列邻域网的空间可以刻划为度量空间在某确定映射下的象。
关键词 序列邻域 CS 1序列覆盖映射 σ点 度量空间
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SDH网中二纤单向通道保护环的自愈功能及应用 被引量:5
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作者 张翠芳 朱莉娟 钱学荣 《电信技术》 2002年第3期68-69,共2页
关键词 同步数字序列网 二纤单向通道保护环 通信 自愈功能
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关于可数网络的注记 被引量:1
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作者 燕鹏飞 朱夜明 《安徽大学学报(自然科学版)》 CAS 1999年第2期5-8,共4页
通过各种可数网的讨论,给出了可分度量空间的1序列覆盖、序列覆盖象的内在刻划。
关键词 序列邻域 R CS 广义度量空间 可数
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Multi-dimension and multi-modal rolling mill vibration prediction model based on multi-level network fusion
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作者 CHEN Shu-zong LIU Yun-xiao +3 位作者 WANG Yun-long QIAN Cheng HUA Chang-chun SUN Jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3329-3348,共20页
Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction mode... Mill vibration is a common problem in rolling production,which directly affects the thickness accuracy of the strip and may even lead to strip fracture accidents in serious cases.The existing vibration prediction models do not consider the features contained in the data,resulting in limited improvement of model accuracy.To address these challenges,this paper proposes a multi-dimensional multi-modal cold rolling vibration time series prediction model(MDMMVPM)based on the deep fusion of multi-level networks.In the model,the long-term and short-term modal features of multi-dimensional data are considered,and the appropriate prediction algorithms are selected for different data features.Based on the established prediction model,the effects of tension and rolling force on mill vibration are analyzed.Taking the 5th stand of a cold mill in a steel mill as the research object,the innovative model is applied to predict the mill vibration for the first time.The experimental results show that the correlation coefficient(R^(2))of the model proposed in this paper is 92.5%,and the root-mean-square error(RMSE)is 0.0011,which significantly improves the modeling accuracy compared with the existing models.The proposed model is also suitable for the hot rolling process,which provides a new method for the prediction of strip rolling vibration. 展开更多
关键词 rolling mill vibration multi-dimension data multi-modal data convolutional neural network time series prediction
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TIME SERIES NEURAL NETWORK MODEL FOR HYDROLOGIC FORECASTING 被引量:4
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作者 钟登华 刘东海 Mittnik Stefan 《Transactions of Tianjin University》 EI CAS 2001年第3期182-186,共5页
Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation proced... Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation procedure for hydrologic forecasting.Free from the disadvantages of previous models,the model can be parallel to operate information flexibly and rapidly.It excels in the ability of nonlinear mapping and can learn and adjust by itself,which gives the model a possibility to describe the complex nonlinear hydrologic process.By using directly a training process based on a set of previous data, the model can forecast the time series of stream flow.Moreover,two practical examples were used to test the performance of the time series neural network model.Results confirm that the model is efficient and feasible. 展开更多
关键词 hydrologic forecasting time series neural network model back propagation
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度量空间的SS映射
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作者 燕鹏飞 李南 《安徽大学学报(自然科学版)》 CAS 1998年第2期1-2,12,共3页
本文利用局部可数簇的概念,给出了度量空间的1序列覆盖SS象和2序列覆盖SS象以刻划。
关键词 局部可数 序列领域 度量空间 SS映射
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σ-局部有限集族与度量空间的σ-映象
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作者 梁洪亮 王庆东 《纯粹数学与应用数学》 CSCD 北大核心 2006年第4期516-519,共4页
利用σ-映射建立了具有σ-局部有限cs-网、σ-局部有限cs*-网、σ-局部有限序列邻域网、σ-局部有限序列开网的空间与度量空间确定的σ-映象之间的联系.
关键词 σ-映射 σ-局部有限集族 CS- cs^*- 序列领域 序列
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关于σ-映射
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作者 李克典 李进金 《商丘师范学院学报》 CAS 2000年第6期48-50,共3页
利用序列覆盖σ 映射建立了具有σ 局部有限cs 网、具有σ
关键词 序列覆盖映射 σ-映射 序列邻域 度量空间
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Prediction of the Helix/Sheet Content of Proteins from Their Primary Sequences by Neural Network Method
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作者 秦红珊 杨新岐 王克起 《Transactions of Tianjin University》 EI CAS 2002年第4期303-307,共4页
The amino acid composition and the biased auto-correlation function are considered as features, BP neural network algorithm is used to synthesize these features. The prediction accuracy of this method is verified by u... The amino acid composition and the biased auto-correlation function are considered as features, BP neural network algorithm is used to synthesize these features. The prediction accuracy of this method is verified by using the independent non-homologous protein database. It is shown that the average absolute errors for resubstitution test are 0.070 and 0.068 with the standard deviations 0.049 and 0.047 for the prediction of the content of α-helix and β-sheet respectively. For cross-validation test, the average absolute errors are 0.075 and 0.070 with the standard deviations 0.050 and 0.049 for the prediction of the content of α-helix and β-sheet respectively. Compared with the other methods currently available, the BP neural network method combined with the amino acid composition and the biased auto-correlation function features can effectively improve the prediction accuracy. 展开更多
关键词 content prediction of α-helix and β-sheet primary sequence BP neural network amino acid composition biased auto-correlation function
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Spaces with σ-locally Countable Weak Bases
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作者 夏省祥 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期37-41,共5页
In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to A... In this paper, by msss_mappings, the relations between metric spaces and spaces with σ _locally countable cs_networks or spaces with σ _locally countable weak bases are established. These are some answers to Alexandroff’s problems. 展开更多
关键词 msss_mapping sequence_covering mapping cs_network weak base
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APPLICATION OF INTELLIGENCE FORECASTING METHOD IN TRAFFIC ANALYSIS OF EGCS 被引量:2
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作者 宗群 岳有军 +1 位作者 曹燕飞 尚晓光 《Transactions of Tianjin University》 EI CAS 2000年第1期18-21,共4页
Traffic flow forecasting is an important part of elevator group control system (EGCS).This paper applies time series prediction theories based on neural networks(NN) to EGCSs traffic analysis,and establishes a time se... Traffic flow forecasting is an important part of elevator group control system (EGCS).This paper applies time series prediction theories based on neural networks(NN) to EGCSs traffic analysis,and establishes a time series NN traffic flow forecasting model.Simulation results show its validity. 展开更多
关键词 traffic flow time series FORECAST elevator group control system neural networks
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Prediction of Gas Emission Based on Infor-mation Fusion and Chaotic Time Series 被引量:15
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作者 GAO Li YU Hong-zhen 《Journal of China University of Mining and Technology》 EI 2006年第1期94-96,共3页
In order to make more exact predictions of gas emissions, information fusion and chaos time series are com- bined to predict the amount of gas emission in pits. First, a multi-sensor information fusion frame is establ... In order to make more exact predictions of gas emissions, information fusion and chaos time series are com- bined to predict the amount of gas emission in pits. First, a multi-sensor information fusion frame is established. The frame includes a data level, a character level and a decision level. Functions at every level are interpreted in detail in this paper. Then, the process of information fusion for gas emission is introduced. On the basis of those data processed at the data and character levels, the chaos time series and neural network are combined to predict the amount of gas emission at the decision level. The weights of the neural network are gained by training not by manual setting, in order to avoid subjectivity introduced by human intervention. Finally, the experimental results were analyzed in Matlab 6.0 and prove that the method is more accurate in the prediction of the amount of gas emission than the traditional method. 展开更多
关键词 gas emission information fusion chaos time series neural network
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Analysis of Petri net model and task planning heuristic algorithms for product reconfiguration 被引量:1
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作者 林春深 Tang Xiaoqiang Duan Guanghong 《High Technology Letters》 EI CAS 2007年第3期254-260,共7页
Reconfiguration planning is recognized as an important factor for reducing the cost of manufacturing reconfigurable products, and the associated main task is to generate a set of optimal or near-optimal reconfiguratio... Reconfiguration planning is recognized as an important factor for reducing the cost of manufacturing reconfigurable products, and the associated main task is to generate a set of optimal or near-optimal reconfiguration sequences using some effect algorithms. A method is developed to generate a Petri net as the reconfiguration tree to represent two-state-transit of product, which solved the representation problem of reconfiguring interfaces replacement. Relating with this method, two heuristic algorithms are proposed to generate task sequences which considering economics to search reconfiguration paths effectively. At last, an objective evaluation is applied to compare these two heuristic algorithms to other ones. The developed reconfiguration task planning heuristic algorithms can generate better strategies and plans for reconfiguration. The research finds are exemplified with struts reconfiguration of reconfigurable parallel kinematics machine (RPKM). 展开更多
关键词 heuristic algorithms reconfiguration planning Petri net parallel kinematics machines
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Time-series analysis with a hybrid Box-Jenkins ARIMA 被引量:2
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作者 Dilli R Aryal 王要武 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第4期413-421,共9页
Time-series analysis is important to a wide range of disciplines transcending both the physical and social sciences for proactive policy decisions. Statistical models have sound theoretical basis and have been success... Time-series analysis is important to a wide range of disciplines transcending both the physical and social sciences for proactive policy decisions. Statistical models have sound theoretical basis and have been successfully used in a number of problem domains in time series forecasting. Due to power and flexibility, Box-Jenkins ARIMA model has gained enormous popularity in many areas and research practice for the last three decades. More recently, the neural networks have been shown to be a promising alternative tool for modeling and forecasting owing to their ability to capture the nonlinearity in the data. However, despite the popularity and the superiority of ARIMA and ANN models, the empirical forecasting performance has been rather mixed so that no single method is best in every situation. In this study, a hybrid ARIMA and neural networks model to time series forecasting is proposed. The basic idea behind the model combination is to use each model’s unique features to capture different patterns in the data. With three real data sets, empirical results evidently show that the hybrid model outperforms ARIMA and ANN model noticeably in terms of forecasting accuracy used in isolation. 展开更多
关键词 time series analysis ARIMA Box-Jenkins methodology artificial neural networks hybrid model
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Nonlinear Time Series Prediction Using Chaotic Neural Networks 被引量:3
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作者 LIKe-Ping CHENTian-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期759-762,共4页
A nonlinear feedback term is introduced into the evaluation equation of weights of the backpropagation algorithm for neural network, the network becomes a chaotic one. For the purpose of that we can investigate how th... A nonlinear feedback term is introduced into the evaluation equation of weights of the backpropagation algorithm for neural network, the network becomes a chaotic one. For the purpose of that we can investigate how the different feedback terms affect the process of learning and forecasting, we use the model to forecast the nonlinear time series which is produced by Makey-Glass equation. By selecting the suitable feedback term, the system can escape from the local minima and converge to the global minimum or its approximate solutions, and the forecasting results are better than those of backpropagation algorithm. 展开更多
关键词 neural network chaotic dynamics forecasting nonlinear time series
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On Point countable Sequential Neighborhood Networks
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作者 李克典 任学军 菅典兵 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第3期88-91, ,共4页
In this paper we prove that a space X with point countable sequential neighborhood network if and only if it is α 4 space with point countable cs network.
关键词 sequential neighborhood sequential neighborhood network cs network α 1 space α 4 space
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Energy-Efficient Target Channel Sequence Design for Spectrum Handoffs in Cognitive Radio Networks 被引量:1
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作者 Xiaolong Yang Xuezhi Tan 《China Communications》 SCIE CSCD 2017年第5期207-217,共11页
Cognitive radio is considered as an efficient way to improve the spectrum efficiency. As one of its key technologies,spectrum handoff can guarantee the transmission continuity of secondary users(SUs). In this paper,we... Cognitive radio is considered as an efficient way to improve the spectrum efficiency. As one of its key technologies,spectrum handoff can guarantee the transmission continuity of secondary users(SUs). In this paper,we address a new and more generalized spectrum handoff problem in cognitive radio networks(CRNs),by considering simultaneously energy efficiency,multiple spectrum handoffs and multiple channels. Furthermore,effects of the primary users'(PUs')arrival and service rate on the target channel sequence selection are also considered. In order to obtain the energy-efficient target channel sequence,we firstly analyze the energy consumption and the number of delivered bits per hertz in the spectrum handoff process,and formulate a ratio-type energy efficiency optimization problem,which can be transformed into a parametric problem by utilizing fractional programming. Then,we propose an algorithm combining dynamic programming with bisection(DPB)algorithm to solve the energy efficiency optimization problem. Our simulation results verify that the designed target channel sequence has better performance than the existing algorithms in terms of energy efficiency. 展开更多
关键词 energy efficiency spectrum handoff: fractional programming cognitive radio networks
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Remaining Useful Life Prediction of Aeroengine Based on Principal Component Analysis and One-Dimensional Convolutional Neural Network 被引量:4
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作者 LYU Defeng HU Yuwen 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第5期867-875,共9页
In order to directly construct the mapping between multiple state parameters and remaining useful life(RUL),and reduce the interference of random error on prediction accuracy,a RUL prediction model of aeroengine based... In order to directly construct the mapping between multiple state parameters and remaining useful life(RUL),and reduce the interference of random error on prediction accuracy,a RUL prediction model of aeroengine based on principal component analysis(PCA)and one-dimensional convolution neural network(1D-CNN)is proposed in this paper.Firstly,multiple state parameters corresponding to massive cycles of aeroengine are collected and brought into PCA for dimensionality reduction,and principal components are extracted for further time series prediction.Secondly,the 1D-CNN model is constructed to directly study the mapping between principal components and RUL.Multiple convolution and pooling operations are applied for deep feature extraction,and the end-to-end RUL prediction of aeroengine can be realized.Experimental results show that the most effective principal component from the multiple state parameters can be obtained by PCA,and the long time series of multiple state parameters can be directly mapped to RUL by 1D-CNN,so as to improve the efficiency and accuracy of RUL prediction.Compared with other traditional models,the proposed method also has lower prediction error and better robustness. 展开更多
关键词 AEROENGINE remaining useful life(RUL) principal component analysis(PCA) one-dimensional convolution neural network(1D-CNN) time series prediction state parameters
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