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A new grey forecasting model based on BP neural network and Markov chain 被引量:6
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作者 李存斌 王恪铖 《Journal of Central South University of Technology》 EI 2007年第5期713-718,共6页
A new grey forecasting model based on BP neural network and Markov chain was proposed. In order to combine the grey forecasting model with neural network, an important theorem that the grey differential equation is eq... A new grey forecasting model based on BP neural network and Markov chain was proposed. In order to combine the grey forecasting model with neural network, an important theorem that the grey differential equation is equivalent to the time response model, was proved by analyzing the features of grey forecasting model(GM(1,1)). Based on this, the differential equation parameters were included in the network when the BP neural network was constructed, and the neural network was trained by extracting samples from grey system's known data. When BP network was converged, the whitened grey differential equation parameters were extracted and then the grey neural network forecasting model (GNNM(1,1)) was built. In order to reduce stochastic phenomenon in GNNM(1,1), the state transition probability between two states was defined and the Markov transition matrix was established by building the residual sequences between grey forecasting and actual value. Thus, the new grey forecasting model(MNNGM(1,1)) was proposed by combining Markov chain with GNNM(1,1). Based on the above discussion, three different approaches were put forward for forecasting China electricity demands. By comparing GM(1, 1) and GNNM(1,1) with the proposed model, the results indicate that the absolute mean error of MNNGM(1,1) is about 0.4 times of GNNM(1,1) and 0.2 times of GM(I, 1), and the mean square error of MNNGM(1,1) is about 0.25 times of GNNM(1,1) and 0.1 times of GM(1,1). 展开更多
关键词 grey forecasting model neural network Markov chain electricity demand forecasting
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A novel recurrent neural network forecasting model for power intelligence center 被引量:6
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作者 刘吉成 牛东晓 《Journal of Central South University of Technology》 EI 2008年第5期726-732,共7页
In order to accurately forecast the load of power system and enhance the stability of the power network, a novel unascertained mathematics based recurrent neural network (UMRNN) for power intelligence center (PIC) was... In order to accurately forecast the load of power system and enhance the stability of the power network, a novel unascertained mathematics based recurrent neural network (UMRNN) for power intelligence center (PIC) was created through three steps. First, by combining with the general project uncertain element transmission theory (GPUET), the basic definitions of stochastic, fuzzy, and grey uncertain elements were given based on the principal types of uncertain information. Second, a power dynamic alliance including four sectors: generation sector, transmission sector, distribution sector and customers was established. The key factors were amended according to the four transmission topologies of uncertain elements, thus the new factors entered the power intelligence center as the input elements. Finally, in the intelligence handing background of PIC, by performing uncertain and recursive process to the input values of network, and combining unascertained mathematics, the novel load forecasting model was built. Three different approaches were put forward to forecast an eastern regional power grid load in China. The root mean square error (ERMS) demonstrates that the forecasting accuracy of the proposed model UMRNN is 3% higher than that of BP neural network (BPNN), and 5% higher than that of autoregressive integrated moving average (ARIMA). Besides, an example also shows that the average relative error of the first quarter of 2008 forecasted by UMRNN is only 2.59%, which has high precision. 展开更多
关键词 load forecasting uncertain element power intelligence center unascertained mathematics recurrent neural network
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Forecasting model of residential load based on general regression neural network and PSO-Bayes least squares support vector machine 被引量:5
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作者 何永秀 何海英 +1 位作者 王跃锦 罗涛 《Journal of Central South University》 SCIE EI CAS 2011年第4期1184-1192,共9页
Firstly,general regression neural network(GRNN) was used for variable selection of key influencing factors of residential load(RL) forecasting.Secondly,the key influencing factors chosen by GRNN were used as the input... Firstly,general regression neural network(GRNN) was used for variable selection of key influencing factors of residential load(RL) forecasting.Secondly,the key influencing factors chosen by GRNN were used as the input and output terminals of urban and rural RL for simulating and learning.In addition,the suitable parameters of final model were obtained through applying the evidence theory to combine the optimization results which were calculated with the PSO method and the Bayes theory.Then,the model of PSO-Bayes least squares support vector machine(PSO-Bayes-LS-SVM) was established.A case study was then provided for the learning and testing.The empirical analysis results show that the mean square errors of urban and rural RL forecast are 0.02% and 0.04%,respectively.At last,taking a specific province RL in China as an example,the forecast results of RL from 2011 to 2015 were obtained. 展开更多
关键词 residential load load forecasting general regression neural network (GRNN) evidence theory PSO-Bayes least squaressupport vector machine
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Electricity price forecasting using generalized regression neural network based on principal components analysis 被引量:1
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作者 牛东晓 刘达 邢棉 《Journal of Central South University》 SCIE EI CAS 2008年第S2期316-320,共5页
A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the mai... A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the main influence on day-ahead price, avoiding the strong correlation between the input factors that might influence electricity price, such as the load of the forecasting hour, other history loads and prices, weather and temperature; then GRNN was employed to forecast electricity price according to the main information extracted by PCA. To prove the efficiency of the combined model, a case from PJM (Pennsylvania-New Jersey-Maryland) day-ahead electricity market was evaluated. Compared to back-propagation (BP) neural network and standard GRNN, the combined method reduces the mean absolute percentage error about 3%. 展开更多
关键词 ELECTRICITY PRICE forecasting GENERALIZED regression neural network principal COMPONENTS analysis
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Forecasting increasing rate of power consumption based on immune genetic algorithm combined with neural network 被引量:1
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作者 杨淑霞 《Journal of Central South University》 SCIE EI CAS 2008年第S2期327-330,共4页
Considering the factors affecting the increasing rate of power consumption, the BP neural network structure and the neural network forecasting model of the increasing rate of power consumption were established. Immune... Considering the factors affecting the increasing rate of power consumption, the BP neural network structure and the neural network forecasting model of the increasing rate of power consumption were established. Immune genetic algorithm was applied to optimizing the weight from input layer to hidden layer, from hidden layer to output layer, and the threshold value of neuron nodes in hidden and output layers. Finally, training the related data of the increasing rate of power consumption from 1980 to 2000 in China, a nonlinear network model between the increasing rate of power consumption and influencing factors was obtained. The model was adopted to forecasting the increasing rate of power consumption from 2001 to 2005, and the average absolute error ratio of forecasting results is 13.521 8%. Compared with the ordinary neural network optimized by genetic algorithm, the results show that this method has better forecasting accuracy and stability for forecasting the increasing rate of power consumption. 展开更多
关键词 IMMUNE GENETIC algorithm neural network power CONSUMPTION INCREASING RATE forecast
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Optimizing neural network forecast by immune algorithm 被引量:2
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作者 杨淑霞 李翔 +1 位作者 李宁 杨尚东 《Journal of Central South University of Technology》 EI 2006年第5期573-576,共4页
Considering multi-factor influence, a forecasting model was built. The structure of BP neural network was designed, and immune algorithm was applied to optimize its network structure and weight. After training the dat... Considering multi-factor influence, a forecasting model was built. The structure of BP neural network was designed, and immune algorithm was applied to optimize its network structure and weight. After training the data of power demand from the year 1980 to 2005 in China, a nonlinear network model was obtained on the relationship between power demand and the factors which had impacts on it, and thus the above proposed method was verified. Meanwhile, the results were compared to those of neural network optimized by genetic algorithm. The results show that this method is superior to neural network optimized by genetic algorithm and is one of the effective ways of time series forecast. 展开更多
关键词 neural network forecast immune algorithm OPTIMIZATION
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Artificial Neural Network for Combining Forecasts
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作者 Shanming Shi, Li D. Xu & Bao Liu(Department of Computer Science, University of Colorado at Boulder, Boulder, CO 80309, USA)(Department of MSIS, Wright State University, Dayton, OH 45435,USA)(Institute of Systems Engineering, Tianjin University, Tianjin 30 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第2期58-64,共7页
This paper proposes artificial neural networks (ANN) as a tool for nonlinear combination of forecasts. In this study, three forecasting models are used for individual forecasts, and then two linear combining methods a... This paper proposes artificial neural networks (ANN) as a tool for nonlinear combination of forecasts. In this study, three forecasting models are used for individual forecasts, and then two linear combining methods are used to compare with the ANN combining method. The comparative experiment using real--world data shows that the prediction by the ANN method outperforms those by linear combining methods. The paper suggests that the ANN combining method can be used as- an alternative to conventional linear combining methods to achieve greater forecasting accuracy. 展开更多
关键词 Artificial neural network forecasting Combined forecasts Nonlinear systems.
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Research on Short-Term Electric Load Forecasting Using IWOA CNN-BiLSTM-TPA Model
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作者 MEI Tong-da SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 北大核心 2025年第1期179-187,共9页
Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devi... Load forecasting is of great significance to the development of new power systems.With the advancement of smart grids,the integration and distribution of distributed renewable energy sources and power electronics devices have made power load data increasingly complex and volatile.This places higher demands on the prediction and analysis of power loads.In order to improve the prediction accuracy of short-term power load,a CNN-BiLSTMTPA short-term power prediction model based on the Improved Whale Optimization Algorithm(IWOA)with mixed strategies was proposed.Firstly,the model combined the Convolutional Neural Network(CNN)with the Bidirectional Long Short-Term Memory Network(BiLSTM)to fully extract the spatio-temporal characteristics of the load data itself.Then,the Temporal Pattern Attention(TPA)mechanism was introduced into the CNN-BiLSTM model to automatically assign corresponding weights to the hidden states of the BiLSTM.This allowed the model to differentiate the importance of load sequences at different time intervals.At the same time,in order to solve the problem of the difficulties of selecting the parameters of the temporal model,and the poor global search ability of the whale algorithm,which is easy to fall into the local optimization,the whale algorithm(IWOA)was optimized by using the hybrid strategy of Tent chaos mapping and Levy flight strategy,so as to better search the parameters of the model.In this experiment,the real load data of a region in Zhejiang was taken as an example to analyze,and the prediction accuracy(R2)of the proposed method reached 98.83%.Compared with the prediction models such as BP,WOA-CNN-BiLSTM,SSA-CNN-BiLSTM,CNN-BiGRU-Attention,etc.,the experimental results showed that the model proposed in this study has a higher prediction accuracy. 展开更多
关键词 Whale Optimization Algorithm Convolutional neural network Long Short-Term Memory Temporal Pattern Attention Power load forecasting
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Improved wavelet neural network combined with particle swarm optimization algorithm and its application 被引量:1
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作者 李翔 杨尚东 +1 位作者 乞建勋 杨淑霞 《Journal of Central South University of Technology》 2006年第3期256-259,共4页
An improved wavelet neural network algorithm which combines with particle swarm optimization was proposed to avoid encountering the curse of dimensionality and overcome the shortage in the responding speed and learnin... An improved wavelet neural network algorithm which combines with particle swarm optimization was proposed to avoid encountering the curse of dimensionality and overcome the shortage in the responding speed and learning ability brought about by the traditional models. Based on the operational data provided by a regional power grid in the south of China, the method was used in the actual short term load forecasting. The results show that the average time cost of the proposed method in the experiment process is reduced by 12.2 s, and the precision of the proposed method is increased by 3.43% compared to the traditional wavelet network. Consequently, the improved wavelet neural network forecasting model is better than the traditional wavelet neural network forecasting model in both forecasting effect and network function. 展开更多
关键词 artificial neural network particle swarm optimization algorithm short-term load forecasting WAVELET curse of dimensionality
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Nerual Network Expert System and Their Application to Forecasting Water Invasion of Colliery
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作者 Zhang Jing & Li Renhou (Computer & Application Group, Xi’an University of Technology, Xi’an 710048, China)(System Engineering Institute of Xi’an JiaoTong University, Xi’an 710049, China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第2期52-57,共6页
In this paper, we propose a formal definition, general structure and work principle of the Neural Network Expert System (NNES) based on joint-type knowledge representation, and show a practical application example usi... In this paper, we propose a formal definition, general structure and work principle of the Neural Network Expert System (NNES) based on joint-type knowledge representation, and show a practical application example using NNES for forecasting the water invasion of coal mine. 展开更多
关键词 neural network Expert system Water calamity forecasting.
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Artificial Intelligence Based Meteorological Parameter Forecasting for Optimizing Response of Nuclear Emergency Decision Support System
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作者 BILAL Ahmed Khan HASEEB ur Rehman +5 位作者 QAISAR Nadeem MUHAMMAD Ahmad Naveed Qureshi JAWARIA Ahad MUHAMMAD Naveed Akhtar AMJAD Farooq MASROOR Ahmad 《原子能科学技术》 EI CAS CSCD 北大核心 2024年第10期2068-2076,共9页
This paper presents a novel artificial intelligence (AI) based approach to predict crucial meteorological parameters such as temperature,pressure,and wind speed,typically calculated from computationally intensive weat... This paper presents a novel artificial intelligence (AI) based approach to predict crucial meteorological parameters such as temperature,pressure,and wind speed,typically calculated from computationally intensive weather research and forecasting (WRF) model.Accurate meteorological data is indispensable for simulating the release of radioactive effluents,especially in dispersion modeling for nuclear emergency decision support systems.Simulation of meteorological conditions during nuclear emergencies using the conventional WRF model is very complex and time-consuming.Therefore,a new artificial neural network (ANN) based technique was proposed as a viable alternative for meteorological prediction.A multi-input multi-output neural network was trained using historical site-specific meteorological data to forecast the meteorological parameters.Comprehensive evaluation of this technique was conducted to test its performance in forecasting various parameters including atmospheric pressure,temperature,and wind speed components in both East-West and North-South directions.The performance of developed network was evaluated on an unknown dataset,and acquired results are within the acceptable range for all meteorological parameters.Results show that ANNs possess the capability to forecast meteorological parameters,such as temperature and pressure,at multiple spatial locations within a grid with high accuracy,utilizing input data from a single station.However,accuracy is slightly compromised when predicting wind speed components.Root mean square error (RMSE) was utilized to report the accuracy of predicted results,with values of 1.453℃for temperature,77 Pa for predicted pressure,1.058 m/s for the wind speed of U-component and 0.959 m/s for the wind speed of V-component.In conclusion,this approach offers a precise,efficient,and wellinformed method for administrative decision-making during nuclear emergencies. 展开更多
关键词 prediction of meteorological parameters weather research and forecasting model artificial neural networks nuclear emergency support system
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Rapid urban flood forecasting based on cellular automata and deep learning
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作者 BAI Bing DONG Fei +1 位作者 LI Chuanqi WANG Wei 《水利水电技术(中英文)》 北大核心 2024年第12期17-28,共12页
[Objective]Urban floods are occurring more frequently because of global climate change and urbanization.Accordingly,urban rainstorm and flood forecasting has become a priority in urban hydrology research.However,two-d... [Objective]Urban floods are occurring more frequently because of global climate change and urbanization.Accordingly,urban rainstorm and flood forecasting has become a priority in urban hydrology research.However,two-dimensional hydrodynamic models execute calculations slowly,hindering the rapid simulation and forecasting of urban floods.To overcome this limitation and accelerate the speed and improve the accuracy of urban flood simulations and forecasting,numerical simulations and deep learning were combined to develop a more effective urban flood forecasting method.[Methods]Specifically,a cellular automata model was used to simulate the urban flood process and address the need to include a large number of datasets in the deep learning process.Meanwhile,to shorten the time required for urban flood forecasting,a convolutional neural network model was used to establish the mapping relationship between rainfall and inundation depth.[Results]The results show that the relative error of forecasting the maximum inundation depth in flood-prone locations is less than 10%,and the Nash efficiency coefficient of forecasting inundation depth series in flood-prone locations is greater than 0.75.[Conclusion]The result demonstrated that the proposed method could execute highly accurate simulations and quickly produce forecasts,illustrating its superiority as an urban flood forecasting technique. 展开更多
关键词 urban flooding flood-prone location cellular automata deep learning convolutional neural network rapid forecasting
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考虑季节性与趋势特征的光伏功率预测模型研究 被引量:1
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作者 王东风 李青博 +1 位作者 张博洋 黄宇 《太阳能学报》 北大核心 2025年第3期348-356,共9页
针对光伏功率预测中未充分考虑光伏功率季节性与趋势特征的问题,提出一种基于Neural-Prophet(NP)与深度神经网络的光伏功率预测方法。首先,通过互信息法筛选出影响光伏功率的主要因素,利用NP模型对光伏功率建模得到光伏功率的季节性与... 针对光伏功率预测中未充分考虑光伏功率季节性与趋势特征的问题,提出一种基于Neural-Prophet(NP)与深度神经网络的光伏功率预测方法。首先,通过互信息法筛选出影响光伏功率的主要因素,利用NP模型对光伏功率建模得到光伏功率的季节性与趋势特征,将季节性与趋势特征及主要影响因素作为模型输入。其次,采用改进残差网络(ResNet)和双向门控循环单元(BiGRU)建立NP-ResNet-BiGRU光伏功率预测模型并完成光伏功率预测。利用春夏秋冬四季的数据进行实验,结果显示相较于其他方法,所提方法的MAE至少提升7.44%,RMSE至少提升4.62%。 展开更多
关键词 光伏发电 预测 神经网络 残差网络 neural-Prophet
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基于GA-LSTM的桥梁缆索腐蚀钢丝力学性能预测模型 被引量:6
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作者 缪长青 吕悦凯 万春风 《东南大学学报(自然科学版)》 北大核心 2025年第1期140-145,共6页
为了精准捕捉桥梁缆索腐蚀钢丝的时变规律并预测其力学性能,开发了一种基于遗传算法(genetic algorithm, GA)优化的长短期记忆(long short-term memory, LSTM)神经网络模型。该模型利用GA依次优化LSTM模型的迭代次数、隐藏层层数、神经... 为了精准捕捉桥梁缆索腐蚀钢丝的时变规律并预测其力学性能,开发了一种基于遗传算法(genetic algorithm, GA)优化的长短期记忆(long short-term memory, LSTM)神经网络模型。该模型利用GA依次优化LSTM模型的迭代次数、隐藏层层数、神经元数量、窗口大小4个超参数,以预测不同腐蚀特征状态下钢丝的力学性能。将其与传统LSTM和GA-反向传播模型的预测结果进行比较。结果表明,GA-LSTM模型具有更高的预测精度和鲁棒性。在屈服强度与极限强度预测效果方面,均方根误差(root mean square error, RMSE)、平均绝对误差(mean absolute error, MAE)、决定系数分别提高约44%~61%、43%~57%、35%~92%。在屈服应变与极限应变预测效果方面,RMSE、MAE、决定系数分别提高约0~46%、7%~49%、12%~229%。所建立的模型可以作为一个有用的工具支持桥梁缆索腐蚀安全性评估工作。 展开更多
关键词 桥梁缆索腐蚀钢丝 力学性能预测 时序预测 神经网络 遗传算法 超参数优化
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基于BiLSTM-AM-ResNet组合模型的山西焦煤价格预测 被引量:1
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作者 樊园杰 睢祎平 张磊 《中国煤炭》 北大核心 2025年第3期42-51,共10页
煤炭作为我国重要的基础能源,其价格的波动会直接影响国民经济发展与能源市场稳定,因此对煤炭价格进行预测具有重要意义。针对我国煤炭价格受政策与供求关系影响大、多呈现非线性的变化趋势,且目前存在的煤价预测方法存在滞后性大等问题... 煤炭作为我国重要的基础能源,其价格的波动会直接影响国民经济发展与能源市场稳定,因此对煤炭价格进行预测具有重要意义。针对我国煤炭价格受政策与供求关系影响大、多呈现非线性的变化趋势,且目前存在的煤价预测方法存在滞后性大等问题,以山西焦煤价格为研究对象,分析影响煤炭价格的多种因素,并利用先进的人工智能机器学习算法来解决煤价预测问题。综合双向长短期记忆网络、注意力机制和残差神经网络的优势,构建双向长短期残差神经网络(BiLSTM-AM-ResNet)进行山西焦煤价格预测实验。采集2012-2023年的山西焦煤价格周度数据作为实验数据,对其进行空缺值处理和归一化处理,绘制相关系数热图并确定模型输入特征类型,进而简化模型并提高预测准确率与预测速度。通过模型预测实验得出,经BiLSTM-AM-ResNet模型预测的山西焦煤价格与实际煤价的发展趋势有着较高的线性拟合性,且预测结果与真实煤价在数值上非常接近,预测准确率达到了95.08%。 展开更多
关键词 焦煤价格预测 长短期记忆网络 注意力机制 残差神经网络 相关性分析
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基于卷积神经网络的湖南盛夏高温过程延伸期智能预报
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作者 张祎 谭桂容 +3 位作者 赵辉 曾玲玲 黄超 费琪铭 《大气科学学报》 北大核心 2025年第4期603-617,共15页
本研究旨在提升湖南省盛夏(7、8月)高温过程的延伸期预报技巧。本文利用1999—2022年湖南省97个站点逐日最高气温资料以及次季节-季节(sub-seasonal to seasonal prediction,S2S)模式数据中欧洲中期天气预报中心(ECMWF)和美国国家环境... 本研究旨在提升湖南省盛夏(7、8月)高温过程的延伸期预报技巧。本文利用1999—2022年湖南省97个站点逐日最高气温资料以及次季节-季节(sub-seasonal to seasonal prediction,S2S)模式数据中欧洲中期天气预报中心(ECMWF)和美国国家环境预报中心(NCEP)两种模式预报产品,并基于模式温度与环流预报产品提取物理因子,结合卷积神经网络(convolutional neural network,CNN)构建了湖南省盛夏高温过程的预报模型(high temperature prediction model,HTPM);对订正后的S2S模式和构建的预报模型结果进行集成,以实现对区域高温过程较为稳定的相对高技巧预报。结果表明:S2S模式的原始预报技巧较低,偏差订正能显著提高预报效果,但存在较高的空报率;基于ECMWF的S2S数据训练的高温预报模型(HTPM-ECS2S)和基于NCEP的S2S数据训练的高温预报模型(HTPM-NCEPS2S)能有效捕捉高温事件,在高温预报中具有较高的预报技巧;集成方案有效整合了多模型优点,可提升预报的准确性和可靠性。 展开更多
关键词 高温过程 延伸期预报 卷积神经网络 集成预报
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基于卷积-长短记忆神经网络的页岩气井短期产量预测与概率性评价
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作者 郭建春 任文希 +3 位作者 曾凡辉 刘彧轩 段又菁 罗扬 《钻采工艺》 北大核心 2025年第1期130-137,共8页
页岩气赋存方式多样、渗流机理复杂,气井生产制度多变,准确预测页岩气井产量难度大。针对这一问题,文章基于数据驱动的思想,对历史生产数据进行了预处理,建立了由产量、油嘴尺寸、生产时间和关井时间组成的多维时间序列,结合卷积神经网... 页岩气赋存方式多样、渗流机理复杂,气井生产制度多变,准确预测页岩气井产量难度大。针对这一问题,文章基于数据驱动的思想,对历史生产数据进行了预处理,建立了由产量、油嘴尺寸、生产时间和关井时间组成的多维时间序列,结合卷积神经网络(CNN)和长短记忆神经网络(LSTM),基于混合式深度学习架构,建立了基于卷积-长短记忆神经网络的页岩气井短期产量预测模型(CNN-LSTM)。CNN-LSTM采用CNN提取高维特征之间的交互作用信息,并利用LSTM提取这些特征的时序信息,实现了交互作用信息和时序信息的融合。生产数据测试表明:CNN-LSTM考虑了生产制度的影响,因此其产量预测精度高于单变量LSTM和多变量LSTM。进一步发展了基于核密度估计理论的产量概率性预测方法,实现了产量预测结果的不确定分析,获得了未来气井产量的变化范围。研究成果有望为页岩气井生产动态分析、产量预测和生产管理提供支撑。 展开更多
关键词 页岩气井 产量预测 神经网络 不确定分析 数据驱动
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基于深度学习的井筒变形预测模型与应用
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作者 刘辉 李国强 +4 位作者 朱晓峻 张鹏飞 程桦 王金正 李培帅 《煤炭学报》 北大核心 2025年第2期732-747,共16页
近年来我国东部矿区发生了多起立井井筒倾斜变形及破损灾害,严重影响了矿井安全与生产。针对厚含水松散层深立井倾斜破损灾害,以鲁南某矿深立井井筒(800 m)为研究对象,开展了井筒倾斜变形监测,研究了井筒倾斜时空变化特征,分析了井筒倾... 近年来我国东部矿区发生了多起立井井筒倾斜变形及破损灾害,严重影响了矿井安全与生产。针对厚含水松散层深立井倾斜破损灾害,以鲁南某矿深立井井筒(800 m)为研究对象,开展了井筒倾斜变形监测,研究了井筒倾斜时空变化特征,分析了井筒倾斜主要影响因素;在此基础上,基于深度学习理论,综合采用循环神经网络(RNN)、长短期记忆网络(LSTM)、门控循环单元(GRU)、一维卷积神经网络(1DCNN)四种经典深度学习方法,构建了井筒倾斜变形预测模型,并将预测结果与实测值进行对比,分析了井筒变形预测模型精度,研究了井筒整体和关键区域预测效果,验证了模型可靠性,并开展了工程应用。研究表明:①井筒倾斜主要发生在松散层,倾斜值由浅到深线性减小、并偏向采空区一侧,最大为352 mm,基岩层变形较小,最大为88 mm;开采引起厚松散层变形传播范围增大、底部含水层沿井壁渗流疏水及地下水渗流场的变化是导致井筒倾斜变形的主要原因。②模型与实测值Spearman相关系数最大为0.978,最小为0.867,4种模型与现场实测偏移量的最大差值为0.043 m,平均绝对误差E_(MA)在0.003~0.009 m内,均方根误差E_(RMS)在0.004~0.011 m内,整体预测效果以1 DCNN模型最优,主要倾斜方向(偏向采空区一侧的东西方向)预测精度略低于变形量较小的方向(南北方向),且均能够满足工程需要。③井筒整体预测曲线与实际倾斜方向一致,井口、松散层基岩交界面E_(MA)与E_(RMS)平均值均为0.005 m、0.006 m,井底精度略低,其对应值为0.012、0.013 m,井筒特征区域与整体预测效果均表现良好,表明基于深度学习的井筒变形预测模型具有良好的预测能力,研究成果在井筒注浆修复治理工程中得到了有效应用,为井筒安全管理提供了技术参考和数据支撑,为类似工程提供了工程实践经验。 展开更多
关键词 煤矿立井 倾斜变形 深度学习 井筒预测 神经网络
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基于WPD-ISSA-CA-CNN模型的电厂碳排放预测
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作者 池小波 续泽晋 +1 位作者 贾新春 张伟杰 《控制工程》 北大核心 2025年第8期1387-1394,共8页
碳排放的准确预测有利于制定合理的碳减排策略。目前,针对电厂碳排放的研究较少,且传统预测模型训练时间过长。基于此,提出一种分量增广输入的WPD-ISSA-CA-CNN碳排放量预测模型,该模型创新性地构建“分解-增广融合预测”策略。首先,利... 碳排放的准确预测有利于制定合理的碳减排策略。目前,针对电厂碳排放的研究较少,且传统预测模型训练时间过长。基于此,提出一种分量增广输入的WPD-ISSA-CA-CNN碳排放量预测模型,该模型创新性地构建“分解-增广融合预测”策略。首先,利用小波包分解(wavelet packet decomposition,WPD)算法将信号按频率特性分解为子序列,再将全部分量增广(component augmentation,CA)作为模型输入,以减少模型的训练时间。其次,考虑到该模型超参数选择困难,利用多策略融合的改进麻雀搜索算法(improved sparrow search algorithm,ISSA)对卷积神经网络(convolutional neural networks,CNNs)的超参数进行寻优。以山西某发电厂2×25 MW锅炉的历史数据为样本,利用5种评价指标将所提模型与BP、LSTM、CNN及其混合模型进行对比。结果表明,所提混合模型在预测火力发电碳排放中各指标均有最佳的准确度且模型训练速度明显提升。 展开更多
关键词 碳排放预测 小波包分解 改进麻雀搜索算法 卷积神经网络
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基于3种时间序列模型的北京市每日花粉浓度预测
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作者 张鑫 杨华 +1 位作者 董玲玲 张宏远 《北京林业大学学报》 北大核心 2025年第6期90-100,共11页
【目的】分析花粉高峰期持续时间和浓度峰值,构建北京市每日花粉浓度的最优预测模型,为科学预测未来每日花粉浓度提供数据支持。【方法】采用多重插补法处理2015—2020年北京市每日花粉浓度时间序列中的缺失数据,2015—2019年数据用于建... 【目的】分析花粉高峰期持续时间和浓度峰值,构建北京市每日花粉浓度的最优预测模型,为科学预测未来每日花粉浓度提供数据支持。【方法】采用多重插补法处理2015—2020年北京市每日花粉浓度时间序列中的缺失数据,2015—2019年数据用于建立SARIMA、LSTM和Prophet 3种时间序列模型,预测未来一年(2020年,共计182 d)的花粉浓度变化。【结果】(1)随机森林法、贝叶斯线性回归法、观测值中随机取样法和加权预测均值匹配法4种多重插补法中,随机森林法的第3个插补数据集P值最小(P=0.002),为最优插补数据集。(2)2015—2020年每日平均花粉浓度数据显示,春季高峰期集中在3—6月,4月初达到峰值(792粒/(103 mm^(2)));秋季高峰期集中在8月至9月末,在9月初达到峰值(449粒/(103 mm^(2)))。2015—2019年花粉浓度总体呈逐年下降趋势,2020年呈现阶跃式上升;其中,2015年高峰期持续时间最长(春季107 d,秋季65 d),2018年最短(春季60 d,秋季46 d);2020年花粉浓度峰值达到最高水平,而2019年花粉浓度峰值最低。(3)3种时间序列模型中,LSTM模型对北京市每日花粉浓度时间序列的描述和预测效果最佳。当LSTM模型的时间步长(look_back)为60时,模型预测效果最佳,RMSE、MAE均为最小,R^(2)=0.78。相比之下,Prophet模型效果较差,无法灵敏捕捉浓度峰值,预测值存在负数情况,预测效果不佳。SARIMA模型拟合效果尚可,但预测效果不理想,预测值存在为负的情况。【结论】与SARIMA和Prophet模型相比,LSTM模型更适用于北京市每日花粉浓度时间序列模型的建立与长期预测。未来研究应完善花粉浓度数据,优化模型性能,以更准确地预测花粉高峰期的起止时间、持续时间及高峰浓度,为过敏性疾病的防控提供更可靠的依据。 展开更多
关键词 多重插补法 花粉浓度 长短期记忆神经网络 长期预测
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