Cheng Sheng

Photovoltaic power forecasting can provide strong support for the safe operation of the power system. Existing forecasting methods are ineffective for grid scheduling decisions or risk analysis. The novel multicluster interval prediction method is proposed to consider the volatility and randomness of PV power output. First, this method utilizes the sparse autoencoder and Bayesian regularized NARX network for point forecasting of PV power. Second, density peak clustering improved by kernel Mahalanobis distance is applied to classify the dataset into multiple clusters, including forecasting error and meteorological factors. Finally, the joint probability density is established by multivariate kernel density estimation to accomplish the PV power interval prediction. The proposed hybrid method is applied for the interval prediction of PV power at Yulara, Australia. Comparative research of point forecasting is implemented to evaluate the machine learning and deep learning methods, with the proposed SAE-BRNARX under four different periods. Results shows that the average values of nRMSE, MRE, nMAE, and R2 for the four periods are 4.45%, 0.90%, −0.15%, 3.39%, and 95.93%, respectively. Moreover, the results of interval prediction obtained by the other interval prediction approaches are compared with the proposed KMDDPC-MKDE. It shows that the average values of PICP, PINAW, ACE, and nMPICD for four periods are 93.93%, 9.50%, 3.93%, and 7.10% at 90% confidence level, respectively. Outcomes demonstrate that the proposed method can obtain more accuracy, a higher coverage rate, narrower average bandwidth, and a closer distance between the middle of interval and actual value than other methods.

The Wang-Chang-Chiang-Yao counterrevolutionary "Gang of Four" carried out revisionism, sowed seeds of discord and resorted to intrigues and plots in an attempt to usurp the Party, seize power, and restore capitalism. Ambition is the source of hypocrisy and falsehood and, of course, of the hypocrisy and falsehood of metaphysics and idealism. The more audacious the "Gang of Four's" ambition to usurp the Party and seize power became, the more barefaced its manifestation of metaphysics and idealism was. Metaphysics and idealism were the faulty ideological weapons they used in the attempt to usurp the Party and seize power. We must follow Chairman Mao's teachings to liquidate the "Gang of Four's" counterrevolutionary revisionist political and ideological line and its crime of impudently trampling on Marxist-Leninist philosophy and Chairman Mao's glorious philosophical thought and protect the purity of Marxism.