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The ice covering of transmission lines tends to cause flashover along the surface, and even topple the tower in serious cases, which seriously threatens the safe operation of the power grid. Here, a dual active and passive anti-icing strategy was designed. The active deicing was achieved by photothermal effect, and passive anti-icing was based on superhydrophobicity. On the one hand, the semi-embedded candle ash gives the surface excellent photothermal characteristics, which can quickly melt the ice through sunlight; On the other hand, the superhydrophobic coating based on candle ash demonstrates excellent passive anti-icing performance, which reduces ice adhesion as small as 3.0 kPa and delayed freezing time as long as 1096 s. Furthermore, the semi-embedded structure enables the superhydrophobic coating excellent anti-abrasion ability and outstanding self-cleaning property. This combination of active and passive anti-icing strategies provides a reference for the current anti-icing and deicing methods of transmission lines.

With the improvement of energy consumption structure, the installed capacity of wind power increases gradually. However, the inherent intermittency and instability of wind energy bring severe challenges to the dispatching operation. Wind power forecasting is one of the main solutions. In this work, a new combined wind power prediction model is proposed. First, a quartile method is used for data cleaning, namely, identifying and eliminating the abnormal data. Then, the wind power data sequence is decomposed by empirical mode decomposition to eliminate non-stationary characteristics. Finally, the wind generator data are trained by the MA-BP network to establish the wind power prediction model. Also, the simulation tests verify the prediction effect of the proposed method. Specifically speaking, the average MAPE is decreased to 12.4979% by the proposed method. Also, the average RMSE and MAE are 107.1728 and 71.604 kW, respectively.

With the further liberalization of the electricity market of China, customers’ requirements, characteristics, and distribution, as well as the quality, security, and reliability of power supplies without interruption, have received considerable attention from power companies, policymakers, and researchers. How to deeply explore the distribution characteristics of electricity customers and analyze their sensitivities to electricity blackouts has become an especially important problem. This paper takes over 0.1 billion data, collected by various smart devices of the Internet of Things in the power system of China, such as smart meters, intelligent power consumption interactive terminals, data concentrators, and other cross-platform data, for example, 95 598 telephone records, complaint information, user bills, user information, and maintenance records, as study objects, to analyze the consumption characteristics of power users. It has been found that there is a wide range of power users who pay different electricity bills; a long-tail distribution following a power law lies in the number of users versus their paid electricity bills. Meanwhile, there are two Pareto effects (2-8 rule): the number of residents and non-residents versus their electricity bills, and the number of large industrial users and general industry (business users) versus in their electricity consumption and bills. Then, a decision tree algorithm is proposed to capture the characteristics of electricity consumers and to recognize the crowd who is power blackout sensitive. The evaluation indexes and parameters of the decision tree are discussed in detail, and a comparison with other intelligent algorithms shows that the decision tree has a good recognition performance over that of others, and the characteristics used to identify the blackout-sensitive crowd is various. All the results state that except for economic factors, positive social effects should also be considered. Various marketing strategies to satisfy different requirements of power users should be provided to promote long-term relationships between the power companies and power customers.

The notable increase in the size and dimensions of data have presented challenges for data storage and retrieval. The Bloom filter and its generations, due to efficient space overheads and constant query delays, have been broadly applied to querying memberships of a big data set. However, the Bloom filter and most of the variants regard each element as a 1-dimensional string and adopt multiple different string hashes to project the data. The interesting problem is when the inputs are numerical vectors with high dimensions, it remains unknown whether they can be projected into the Bloom filter in their original format. Furthermore, we investigate whether the projection is random and uniform. To address these problems, this paper presents a new uniform Prime-HD-BKDERhash family and a new Bloom filter (P-HDBF) to retrieve the membership of a big data set with the numerical high dimensions. Since the randomness and uniformity of data mapping determines the performance of the Bloom filter, to verify these properties, we first introduce information entropy. Our theoretical and experimental results show that the P-HDBF can randomly and uniformly map the data in their native formats. Moreover, the P-HDBF provides an efficient solution alternative to implement membership search with space-time overheads. This advantage may be suitable for engineering applications that are resource-constrained or identification of the nuances of the graphics and images.

Regardless of the type of data, traditional Bloom filters treat each element of a set as a string, and by iterating every character of the string, they discretize all data randomly and uniformly. However, with the data size and dimension increases, these variants are inefficient. To better discretize vectors with high numerical dimensions, this paper improves the string hashes to integer hashes. Based on the integer hashes and a counter array, we propose a new variant—high-dimensional bloom filter (HDBF)—to extend the Bloom filter into high-dimensional spaces, which can represent and query numerical vectors of a big set with a low false positive probability. This paper theoretically analyzes the feasibility of the integer hashes on discretizing data and discusses the relationship of parameters of the HDBF. The experiments illustrate that, in high-dimensional numerical spaces, the HDBF shows better randomness on distribution and entropy than that of the counting Bloom filter. Compared with the parallel Bloom filters, for a fixed false positive probability, the HDBF displays time-space overheads, and is more suitable to deal with the numerical vectors with high dimensions.