According to the chaotic and non-linear characters of power load data,the time series matrix is established with the theory of phase-space reconstruction,and then Lyapunov exponents with chaotic time series are comput...According to the chaotic and non-linear characters of power load data,the time series matrix is established with the theory of phase-space reconstruction,and then Lyapunov exponents with chaotic time series are computed to determine the time delay and the embedding dimension.Due to different features of the data,data mining algorithm is conducted to classify the data into different groups.Redundant information is eliminated by the advantage of data mining technology,and the historical loads that have highly similar features with the forecasting day are searched by the system.As a result,the training data can be decreased and the computing speed can also be improved when constructing support vector machine(SVM) model.Then,SVM algorithm is used to predict power load with parameters that get in pretreatment.In order to prove the effectiveness of the new model,the calculation with data mining SVM algorithm is compared with that of single SVM and back propagation network.It can be seen that the new DSVM algorithm effectively improves the forecast accuracy by 0.75%,1.10% and 1.73% compared with SVM for two random dimensions of 11-dimension,14-dimension and BP network,respectively.This indicates that the DSVM gains perfect improvement effect in the short-term power load forecasting.展开更多
利用各类算法对非平衡数据进行处理已成为数据挖掘领域研究的热问题。针对非平衡数据的特点,在研究支持向量机的相关理论及K-SVM算法基础上,提出基于惩罚机制的PFKSVM(K-SVMbased on penalty factor)算法,克服K-SVM在最优分类面附近易...利用各类算法对非平衡数据进行处理已成为数据挖掘领域研究的热问题。针对非平衡数据的特点,在研究支持向量机的相关理论及K-SVM算法基础上,提出基于惩罚机制的PFKSVM(K-SVMbased on penalty factor)算法,克服K-SVM在最优分类面附近易发生错分的问题;并提出由重构采样层、基本训练层和综合判定层组成的集成学习模型。利用UCI公共数据集的实验验证了PFKSVM算法及集成模型在处理非平衡数据分类时的优势。展开更多
基金Project(70671039) supported by the National Natural Science Foundation of China
文摘According to the chaotic and non-linear characters of power load data,the time series matrix is established with the theory of phase-space reconstruction,and then Lyapunov exponents with chaotic time series are computed to determine the time delay and the embedding dimension.Due to different features of the data,data mining algorithm is conducted to classify the data into different groups.Redundant information is eliminated by the advantage of data mining technology,and the historical loads that have highly similar features with the forecasting day are searched by the system.As a result,the training data can be decreased and the computing speed can also be improved when constructing support vector machine(SVM) model.Then,SVM algorithm is used to predict power load with parameters that get in pretreatment.In order to prove the effectiveness of the new model,the calculation with data mining SVM algorithm is compared with that of single SVM and back propagation network.It can be seen that the new DSVM algorithm effectively improves the forecast accuracy by 0.75%,1.10% and 1.73% compared with SVM for two random dimensions of 11-dimension,14-dimension and BP network,respectively.This indicates that the DSVM gains perfect improvement effect in the short-term power load forecasting.
文摘利用各类算法对非平衡数据进行处理已成为数据挖掘领域研究的热问题。针对非平衡数据的特点,在研究支持向量机的相关理论及K-SVM算法基础上,提出基于惩罚机制的PFKSVM(K-SVMbased on penalty factor)算法,克服K-SVM在最优分类面附近易发生错分的问题;并提出由重构采样层、基本训练层和综合判定层组成的集成学习模型。利用UCI公共数据集的实验验证了PFKSVM算法及集成模型在处理非平衡数据分类时的优势。