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Hourly traffic flow forecasting using a new hybrid modelling method 被引量:10
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作者 LIU Hui ZHANG Xin-yu +2 位作者 YANG Yu-xiang LI Yan-fei YU Cheng-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第4期1389-1402,共14页
Short-term traffic flow forecasting is a significant part of intelligent transportation system.In some traffic control scenarios,obtaining future traffic flow in advance is conducive to highway management department t... Short-term traffic flow forecasting is a significant part of intelligent transportation system.In some traffic control scenarios,obtaining future traffic flow in advance is conducive to highway management department to have sufficient time to formulate corresponding traffic flow control measures.In hence,it is meaningful to establish an accurate short-term traffic flow method and provide reference for peak traffic flow warning.This paper proposed a new hybrid model for traffic flow forecasting,which is composed of the variational mode decomposition(VMD)method,the group method of data handling(GMDH)neural network,bi-directional long and short term memory(BILSTM)network and ELMAN network,and is optimized by the imperialist competitive algorithm(ICA)method.To illustrate the performance of the proposed model,there are several comparative experiments between the proposed model and other models.The experiment results show that 1)BILSTM network,GMDH network and ELMAN network have better predictive performance than other single models;2)VMD can significantly improve the predictive performance of the ICA-GMDH-BILSTM-ELMAN model.The effect of VMD method is better than that of EEMD method and FEEMD method.To conclude,the proposed model which is made up of the VMD method,the ICA method,the BILSTM network,the GMDH network and the ELMAN network has excellent predictive ability for traffic flow series. 展开更多
关键词 traffic flow forecasting intelligent transportation system imperialist competitive algorithm variational mode decomposition group method of data handling bi-directional long and short term memory ELMAN
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Hybrid LEAP modeling method for long-term energy demand forecasting of regions with limited statistical data 被引量:4
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作者 CHEN Rui RAO Zheng-hua LIAO Sheng-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2136-2148,共13页
An accurate long-term energy demand forecasting is essential for energy planning and policy making. However, due to the immature energy data collecting and statistical methods, the available data are usually limited i... An accurate long-term energy demand forecasting is essential for energy planning and policy making. However, due to the immature energy data collecting and statistical methods, the available data are usually limited in many regions. In this paper, on the basis of comprehensive literature review, we proposed a hybrid model based on the long-range alternative energy planning (LEAP) model to improve the accuracy of energy demand forecasting in these regions. By taking Hunan province, China as a typical case, the proposed hybrid model was applied to estimating the possible future energy demand and energy-saving potentials in different sectors. The structure of LEAP model was estimated by Sankey energy flow, and Leslie matrix and autoregressive integrated moving average (ARIMA) models were used to predict the population, industrial structure and transportation turnover, respectively. Monte-Carlo method was employed to evaluate the uncertainty of forecasted results. The results showed that the hybrid model combined with scenario analysis provided a relatively accurate forecast for the long-term energy demand in regions with limited statistical data, and the average standard error of probabilistic distribution in 2030 energy demand was as low as 0.15. The prediction results could provide supportive references to identify energy-saving potentials and energy development pathways. 展开更多
关键词 energy demand forecasting with limited data hybrid LEAP model ARIMA model Leslie matrix Monte-Carlo method
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Dynamic programming methodology for multi-criteria group decision-making under ordinal preferences 被引量:3
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作者 Wu Li Guanqi Guo +1 位作者 Chaoyuan Yue Yong Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期975-980,共6页
A method of minimizing rankings inconsistency is proposed for a decision-making problem with rankings of alternatives given by multiple decision makers according to multiple criteria. For each criteria, at first, the ... A method of minimizing rankings inconsistency is proposed for a decision-making problem with rankings of alternatives given by multiple decision makers according to multiple criteria. For each criteria, at first, the total inconsistency between the rankings of all alternatives for the group and the ones for every decision maker is defined after the decision maker weights in respect to the criteria are considered. Similarly, the total inconsistency between their final rankings for the group and the ones under every criteria is determined after the criteria weights are taken into account. Then two nonlinear integer programming models minimizing respectively the two total inconsistencies above are developed and then transformed to two dynamic programming models to obtain separately the rankings of all alternatives for the group with respect to each criteria and their final rankings. A supplier selection case illustrated the proposed method, and some discussions on the results verified its effectiveness. This work develops a new measurement of ordinal preferences’ inconsistency in multi-criteria group decision-making (MCGDM) and extends the cook-seiford social selection function to MCGDM considering weights of criteria and decision makers and can obtain unique ranking result. 展开更多
关键词 multi-criteria group decision-making (MCGDM) ordinal preference minimum deviation method dynamic programming Cook-Seiford social selection function.
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Forecasting available parking space with largest Lyapunov exponents method 被引量:3
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作者 季彦婕 汤斗南 +2 位作者 郭卫红 BLYTHE T.Phil 王炜 《Journal of Central South University》 SCIE EI CAS 2014年第4期1624-1632,共9页
The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of ... The techniques to forecast available parking space(APS) are indispensable components for parking guidance systems(PGS). According to the data collected in Newcastle upon Tyne, England, the changing characteristics of APS were studied. Thereafter, aiming to build up a multi-step APS forecasting model that provides richer information than a conventional one-step model, the largest Lyapunov exponents(largest LEs) method was introduced into PGS. By experimental tests conducted using the same dataset, its prediction performance was compared with traditional wavelet neural network(WNN) method in both one-step and multi-step processes. Based on the results, a new multi-step forecasting model called WNN-LE method was proposed, where WNN, which enjoys a more accurate performance along with a better learning ability in short-term forecasting, was applied in the early forecast steps while the Lyapunov exponent prediction method in the latter steps precisely reflect the chaotic feature in latter forecast period. The MSE of APS forecasting for one hour time period can be reduced from 83.1 to 27.1(in a parking building with 492 berths) by using largest LEs method instead of WNN and further reduced to 19.0 by conducted the new method. 展开更多
关键词 available parking space Lyapunov exponents wavelet neural network multi-step forecasting method
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Study and application of time series forecasting based on rough set and Kernel method
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作者 杨淑霞 《Journal of Central South University》 SCIE EI CAS 2008年第S2期336-340,共5页
A support vector machine time series forecasting model based on rough set data preprocessing was proposed by combining rough set attribute reduction and support vector machine regression algorithm. First, remove the r... A support vector machine time series forecasting model based on rough set data preprocessing was proposed by combining rough set attribute reduction and support vector machine regression algorithm. First, remove the redundant attribute for forecasting from condition attribute by rough set method; then use the minimum condition attribute set obtained after the reduction and the corresponding initial data, reform a new training sample set which only retain the important attributes influencing the forecasting accuracy; study and train the support vector machine with the training sample obtained after reduction, and then input the reformed testing sample set according to the minimum condition attribute and corresponding initial data. The model was tested and the mapping relation was got between the condition attribute and forecasting variable. Eventually, power supply and demand were forecasted in this model. The average absolute error rates of power consumption of the whole society and yearly maximum load are respectively 14.21% and 13.23%. It shows that RS-SVM time series forecasting model has high forecasting accuracy. 展开更多
关键词 KERNEL method support VECTOR MACHINE ROUGH SET forecasting
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Analysis on decision-making model of plan evaluation based on grey relation projection and combination weight algorithm 被引量:12
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作者 ZHANG Zhicai CHEN Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第4期789-796,共8页
In military service joint operations, when there are more operational forces, more multifarious materials are consumed, the support is more complex and fuzzy, the deployment of personnel is more rapid, and the support... In military service joint operations, when there are more operational forces, more multifarious materials are consumed, the support is more complex and fuzzy, the deployment of personnel is more rapid, and the support provided by wartime military material support powers can be more effective. When the principles,requirements, influencing factors and goals of military material support forces are deployed in wartime, an evaluation indicator system is established. Thus, a new combined empowerment method based on an analytic hierarchy process(AHP) is developed to calculate the subjective weights, and the rough entropy method is used to calculate the objective weights. Combination weights can be obtained by calculating the weight preference coefficient error, which is determined by combining the cooperative game method and the minimum deviation into objectives. This approach can determine the grey relation projection coefficient and synthesize the measure scheme superiority to finally optimize the deployment plan using the grey relation projection decision-making method. The results show that the method is feasible and effective;it can provide a more scientific and practical decision-making basis for the military material support power deployment in wartime. 展开更多
关键词 method for grey relation projection decision-making military supply power in war deployment plan optimization ana-lytic hierarchy process (AHP) rough entropy method
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Ranking environmental projects model based on multicriteria decision-making and the weight sensitivity analysis 被引量:5
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作者 Jiang Yan Tian Dagang Pan Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期534-539,共6页
With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental qua... With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports' information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals (WSI), the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them. 展开更多
关键词 multicriteria decision-making ranking environmental projects model PROMETHEE method sensitivity analysis weight stability intervals.
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Nonlinear combined forecasting model based on fuzzy adaptive variable weight and its application 被引量:1
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作者 蒋爱华 梅炽 +1 位作者 鄂加强 时章明 《Journal of Central South University》 SCIE EI CAS 2010年第4期863-867,共5页
In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using concept... In order to enhance forecasting precision of problems about nonlinear time series in a complex industry system,a new nonlinear fuzzy adaptive variable weight combined forecasting model was established by using conceptions of the relative error,the change tendency of the forecasted object,gray basic weight and adaptive control coefficient on the basis of the method of fuzzy variable weight.Based on Visual Basic 6.0 platform,a fuzzy adaptive variable weight combined forecasting and management system was developed.The application results reveal that the forecasting precisions from the new nonlinear combined forecasting model are higher than those of other single combined forecasting models and the combined forecasting and management system is very powerful tool for the required decision in complex industry system. 展开更多
关键词 nonlinear combined forecasting nonlinear time series method of fuzzy adaptive variable weight relative error adaptive control coefficient
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Regional landslide forecasting model using interferometric SAR images
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作者 董育烦 张发明 +1 位作者 高正夏 蒯志要 《Journal of Central South University》 SCIE EI CAS 2008年第S2期168-173,共6页
Method of obtaining landslide evaluating information by using Interferometric Synthetic Aperture Radar (InSAR) technique was discussed. More precision landslide surface deformation data extracted from InSAR image need... Method of obtaining landslide evaluating information by using Interferometric Synthetic Aperture Radar (InSAR) technique was discussed. More precision landslide surface deformation data extracted from InSAR image need take suitable SAR interferometric data selecting, path tracking, phase unwrapping processes. Then, the DEM model of scope and surface shape of the landslide was built. Combining with geological property of landslide and sliding displacements obtained from InSAR/D-InSAR images, a new landslide forecasting model called equal central angle slice method for those not obviously deformed landslides was put forward. This model breaks the limits of traditional research methods of geology. In this model, the landslide safety factor was calculated by equal central angle slice method, then considering the persistence ratio of the sliding surface based on plastic theory, the minimum safety factor was the phase when plastic area were complete persistence. This new model makes the application of InSAR/D-InSAR technology become more practical in geology hazard research. 展开更多
关键词 INSAR LANDSLIDE forecasting equal central ANGLE SLICE method monitoring and evaluation model
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The Research on and Application of the Multi-regression Technique in the Course of the Marketing Decision-making of Enterprises
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作者 QIU Xiao-dong, ZHAO Ping (School of Economics & Management, Tsinghua University, Beijing 100084 , China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期221-222,共2页
The reformation of the economy system has led the f un ctional department and status of the enterprises into a variable state. Under th e condition of the market economy, the kernel of the enterprises’ functional dep... The reformation of the economy system has led the f un ctional department and status of the enterprises into a variable state. Under th e condition of the market economy, the kernel of the enterprises’ functional dep artment has diverted to that of marketing decision-making, which face to market and meet with the need of consumption. Assuredly, the kernel of marketing decis ion-making is to prognosticate the future market demand of the production of en terprises accurately, so that it can ensure and realize the maximum of the enter prises’ profit increase. Using empirical research and the multi-regression technique, this paper ana lyzes the enterprises’ production demand forecast of the GMC (Global Management Challenge, held every year globally) and changes most of uncontrollable factors of demand forecast to the controllable ones of the enterprises. The method we us ed to forecast demand by using the multi-regression technique is as follows: 1. Look for the main factors which influence the demand of productions; 2. Establish the regression model; 3. Using the historical data, find the resolution of the correlative index an d do the prominent test; 4. Analyze and compare, regression, adjust parameter and optimize the regress ion model. Our method will make the forecast data closer to the actual prices of the future market requirement quantity in the production marketing decision-making of the enterprises and realize the optimizing combination and the working object w ith the minimum of the cost and the maximum of the profit. And it can ensure the realization of the equity maximum of the enterprises and increase the lifecycle of the production. 展开更多
关键词 marketing decision-making demand forecast corr elative index multi-regression technique
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集合预报进展、挑战及展望
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作者 陈静 朱跃建 +11 位作者 段晚锁 智协飞 闵锦忠 李晓莉 邓国 袁慧玲 冯杰 杜钧 李巧萍 龚建东 沈学顺 穆穆 《气象学报》 北大核心 2025年第3期480-502,共23页
系统概述了集合预报的发展历程和中外主要的集合预报方法,重点回顾了中国全球/区域集合预报系统的发展历程、集合预报系统业务技术、初值扰动技术、模式扰动技术和集合预报应用的进步,以及与当前国际主要数值预报中心集合预报水平的对... 系统概述了集合预报的发展历程和中外主要的集合预报方法,重点回顾了中国全球/区域集合预报系统的发展历程、集合预报系统业务技术、初值扰动技术、模式扰动技术和集合预报应用的进步,以及与当前国际主要数值预报中心集合预报水平的对比。针对集合预报系统逐步走向对流尺度、人工智能模型的趋势,从业务、科研、人工智能与集合预报、天气与气候一体化以及用户需求等方面分析了集合预报技术发展面临的主要挑战,并对未来发展做了展望。 展开更多
关键词 集合预报 方法 中国集合预报 回顾
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基于不同目标函数的WRF-Hydro模型参数敏感性研究 被引量:1
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作者 谷黄河 石怀轩 +2 位作者 孙敏涛 丁震 顾苏烨 《中国农村水利水电》 北大核心 2025年第1期61-69,共9页
水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计... 水文与气象预报相结合可以有效提高洪水预报的精度和延长预见期,陆气耦合模型已成为水文气象学者研究的重点。WRF-Hydro模型作为新一代分布式陆气耦合模型在多尺度洪水预报中具有广阔的应用前景,但由于各物理过程参数化方案复杂,模型计算量大,对该模型的参数敏感性研究还不充分,也影响着模型的模拟精度。研究以湿润区的新安江上游屯溪流域为研究对象,构建多个单目标和多目标函数,并结合Morris全局参数敏感性分析方法,探究了WRF-Hydro模型在不同目标函数下的参数敏感性。结果表明:土壤参数(DKSAT、SMCMAX、BEXP)主要影响壤中流和地表径流,对径流量影响显著,尤其DKSAT最为敏感,直接影响水在土壤中的下渗速度,增大时基流量显著增高而洪峰流量则明显降低;产流参数(SLOPE、REFKDT)主要影响地表径流和基流分配,对洪水过程线形状有重要影响;河道汇流参数ManN影响汇流速度并主要控制峰现时间;植被参数MP对于总水量有一定影响;坡面汇流参数OVROUGHRTFAC和地下水参数Zmax则最不敏感。不同目标函数下的参数敏感性顺序和最优参数取值有一定差异,单目标函数中以相对误差为优化目标会更侧重于全年径流总量和低流量部分的模拟精度,而以效率系数和Kling-Gupta系数为目标则更侧重于场次洪水和高流量部分的模拟效果;基于几个单目标函数组合的多目标函数综合考虑了不同目标函数的影响,结果在一定程度上优于单目标函数。研究可为合理确定WRF-Hydro模型参数优化策略提供参考。 展开更多
关键词 WRF-Hydro模型 Morris法 敏感性分析 多目标函数 洪水预报
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基于季节分解组合模型的全国航空货运量预测 被引量:1
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作者 石学刚 邬林江 范棋航 《科学技术与工程》 北大核心 2025年第13期5655-5661,共7页
为应对日益复杂多变的市场环境带来的航空货运市场供需不平衡问题,提高航空货运量预测精度对于航线规划和供应链优化等具有重要意义。首先基于2000年1月—2022年12月的月度航空货运数据作为训练集,通过季节性分解法(seasonal and trend ... 为应对日益复杂多变的市场环境带来的航空货运市场供需不平衡问题,提高航空货运量预测精度对于航线规划和供应链优化等具有重要意义。首先基于2000年1月—2022年12月的月度航空货运数据作为训练集,通过季节性分解法(seasonal and trend decomposition using loess, STL)捕捉季节性波动规律和长期变化趋势,然后基于深度学习的时间序列预测模型(long short-term memory-support vector regression, LSTM-SVR)来拟合因突发事件下的货运量引起的非线性变化,最后基于2023年全年的月度数据对预测模型进行检验。结果表明:基于季节和组合预测模型(STL-SVR-LSTM)相比于传统方法如自回归移动平均(autoregressive integrated moving average, ARIMA)、SVR或LSTM在突发事件下对航空货运量的预测更为准确。2023年的数据检验得出季节和组合预测模型均方根误差和平均绝对百分比误差分别为3.53和3.53%,拟合优度为0.79,LSTM模型预测结果次优,均方根误差和平均绝对百分比误差分别为5.66和7.73%,拟合优度为0.58,显著优于其他两种传统预测模型。可见该预测模型能适应复杂环境下的航空货运量预测,有助于在突发事件下为企业经营和增强供应链的稳定提供参考建议。 展开更多
关键词 航空运输 月度货运量预测 STL-SVR-LSTM模型 突发事件 预测方法优化
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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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基于系统响应的马斯京根连续演算误差修正方法
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作者 司伟 黄思琦 +5 位作者 瞿思敏 张永康 程翔 朱彦泽 李昂 郑佳乐 《水资源保护》 北大核心 2025年第5期89-95,共7页
针对近年来径流式电站、船闸等河道型水利工程持续修建导致传统马斯京根法在新安江模型流域洪水预报应用中精度下降的问题,引入并改进了系统响应误差修正方法,提出了基于系统响应的马斯京根连续演算误差修正方法。该方法根据预报断面实... 针对近年来径流式电站、船闸等河道型水利工程持续修建导致传统马斯京根法在新安江模型流域洪水预报应用中精度下降的问题,引入并改进了系统响应误差修正方法,提出了基于系统响应的马斯京根连续演算误差修正方法。该方法根据预报断面实测流量和计算流量的差值计算修正比例系数,将其应用于各河段节点,对河道汇流初值进行实时动态修正。以受梯级船闸影响的富春江流域主河道为例进行实例分析,结果表明:修正后的洪水预报精度明显提高,修正方法对洪峰的修正效果最好,对于双峰或多峰洪水,特别是受水利工程调控影响较大的洪水过程具有显著的修正效果;传统马斯京根法在加入系统响应误差修正方法后,可有效降低河道型水利工程对洪水预报中河道汇流演算的影响,提高流域洪水预报精度,同时解决了传统系统响应误差修正方法中信息来源与待修正变量之间信息维度不对称的问题。 展开更多
关键词 洪水预报 马斯京根法 系统响应 误差修正 河道汇流演算 富春江流域
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突发公共卫生事件下感染人数与需求预测
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作者 王付宇 叶惠芬 李艳 《安全与环境学报》 北大核心 2025年第10期3913-3922,共10页
当突发公共卫生事件发生后,由于其传播规律不明确和供需信息不对称等问题使得医疗物资的保障问题突显。研究通过预测突发公共卫生事件的发展情况,为建立应急医疗物资需求预测模型以确保稳定的物资保障提供重要基础。研究提出了易感者-... 当突发公共卫生事件发生后,由于其传播规律不明确和供需信息不对称等问题使得医疗物资的保障问题突显。研究通过预测突发公共卫生事件的发展情况,为建立应急医疗物资需求预测模型以确保稳定的物资保障提供重要基础。研究提出了易感者-暴露者-感染者-康复者-死亡者(Susceptible-Exposed-Infectious-Recovered-Death,SEIRD)模型和遗传算法(Genetic Algorithm,GA)改进的长短期记忆(Long Short-Term Memory,LSTM)神经网络相结合的SEIRD-GA-LSTM模型,实现了对疫情多阶段、多尺度的预测。实例分析结果显示:基于SEIRD-GA-LSTM的组合预测方法准确率较高,验证了模型的有效性和稳健性。 展开更多
关键词 公共安全 多阶段预测 易感者-暴露者-感染者-康复者-死亡者模型 遗传算法改进的长短期记忆网络 组合预测方法
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融合相似预报方法在陇东南短期强降水预报中的应用 被引量:1
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作者 黄晓远 李旭 +2 位作者 杜梦莹 叶培龙 李艳 《高原气象》 北大核心 2025年第1期214-223,共10页
基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进... 基于逐步过滤相似法和自组织映射(SOM)神经网络方法,提出了一种融合相似预报方法。利用ECMWF模式预报产品、ERA5再分析资料和地面气象台站观测数据,使用该方法对2021-2022年陇东南地区开展了时效为72 h的强降水预报试验,并对预报效果进行了检验。结果表明:(1)融合相似预报方法的TS评分处于4.5%~9.1%之间,与ECMWF模式预报结果相比表现出一定的优势。随着预报时效的增长,强降水预报的TS评分呈现减小的趋势,其在08:00(北京时,下同)起报的TS评分相对较高。(2)相比于单独使用逐步过滤相似预报,融合相似预报方法的准确性有所提升,并能在一定程度上降低空报率。其中08:00起报和20:00起报的TS评分提高了1.31%和0.63%,而FAR同时下降了2.39%和1.25%。 展开更多
关键词 强降水 短期预报 相似预报 逐步过滤相似 自组织映射(SOM)
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基于定额法的滁州市需水量预测
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作者 陈小凤 《绿色科技》 2025年第6期102-107,共6页
江淮丘陵地区是安徽省缺水地区之一,合理开展需水量预测对于支撑社会经济可持续发展具有重要意义。本次以滁州市作为研究区域,采用定额法开展需水量预测。根据社会经济现状及产业发展规划等,开展人口、农业、工业等社会经济发展指标预... 江淮丘陵地区是安徽省缺水地区之一,合理开展需水量预测对于支撑社会经济可持续发展具有重要意义。本次以滁州市作为研究区域,采用定额法开展需水量预测。根据社会经济现状及产业发展规划等,开展人口、农业、工业等社会经济发展指标预测。结合现状年用水效率、用水管理等要求,确定2035年滁州市生活、工业、农业用水定额,预测生活、工业、农业和生态需水量。结果表明:2035年滁州市需水总量为28.921亿m 3,预测结果基本符合行业发展规划、用水定额管理要求。研究成果可为区域水资源合理配置、水资源管理提供支撑。 展开更多
关键词 需水量预测 定额法 合理性分析 滁州市
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湖南省主汛期5—8月降水过程延伸期智能预报 被引量:1
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作者 曾玲玲 谭桂容 +3 位作者 赵辉 张祎 黄超 费麒铭 《大气科学学报》 北大核心 2025年第3期486-498,共13页
延伸期预报(提前10~30 d的天气预报)是目前尚未解决而又亟需解决的预报问题之一。本文利用2005—2022年湖南省97站逐日降水资料以及次季节至季节(subseasonal-to-seasonal,S2S)欧洲中期天气预报中心(ECMWF)和美国国家环境预报中心(NCEP... 延伸期预报(提前10~30 d的天气预报)是目前尚未解决而又亟需解决的预报问题之一。本文利用2005—2022年湖南省97站逐日降水资料以及次季节至季节(subseasonal-to-seasonal,S2S)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,并分别以2005—2018年和2019—2022年为训练验证和独立预测年。基于模式的降水与环流预报产品,首先采用分级累积概率匹配和低频阈值法,对模式降水预报进行订正;然后通过分析大尺度环流特征与降水场的耦合关系,结合卷积神经网络(convolutional neural network,CNN)技术,分别构建基于ECMWF和NCEP动态预报产品的降水预测模型;最后对多种模型的预测结果进行集成,优化预测结果。试验结果表明,经过订正的两种模式延伸期降水预报的准确性均有显著提升,其中NCEP模式预报技巧的改进大于ECMWF模式。具体而言,订正后的NCEP模式单站降水预报TS评分提升38.5%,区域降水评分提升43.9%;ECMWF模式的TS评分提升14.0%,区域降水评分提升24.2%。独立预测表明,ECMWF模式预报的准确性要优于NCEP模式,特别是15 d预报时效前。CNN模型在15~30 d预报中展现出超越单一数值模式的预测能力,基于动力模式和CNN模型优势的集成预测在整个延伸期预报时效内均展现出较高的预报技巧。 展开更多
关键词 偏差订正 卷积神经网络 延伸期预报 最优集成方法 降水预报
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不同误差校正方法在衢江流域洪水预报中的应用对比 被引量:1
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作者 杨雨蒙 石朋 +3 位作者 瞿思敏 吴洪石 孙逸群 樊鑫洋 《河海大学学报(自然科学版)》 北大核心 2025年第3期8-14,共7页
采用新安江模型模拟洪水过程,基于纳什效率系数、洪峰相对误差、峰现时间误差等指标评估了实时校正量法、反馈模拟实时校正法、误差自回归模型、随机森林、k最邻近算法和人工神经网络共6种实时校正方法对钱塘江衢江流域洪水预报结果的... 采用新安江模型模拟洪水过程,基于纳什效率系数、洪峰相对误差、峰现时间误差等指标评估了实时校正量法、反馈模拟实时校正法、误差自回归模型、随机森林、k最邻近算法和人工神经网络共6种实时校正方法对钱塘江衢江流域洪水预报结果的校正效果。结果表明:6种校正方法均能减少洪峰相对误差,其中随机森林最优,实时校正量法和反馈模拟法次之;对于纳什效率系数,人工神经网络和误差自回归表现较好,在起始预报时刻距离洪峰较远时,人工神经网络的效果更好;对于峰现时间,随机森林的校正效果最好,其次是人工神经网络;各方法综合比较而言,人工神经网络的表现最好,可以在一定程度上提高洪水预报的精度。 展开更多
关键词 洪水预报 实时校正 误差自回归 反馈模拟实时校正法 机器学习 新安江模型 衢江流域
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