Applied Mechanics and Materials Vol. 340

Abstract: Not only distribution automation system but the principle of the existing means of communication are studied systematically and distribution automation communication system model based on IP network is provided. Backbone network is set between master station in the control center and substation sub-station. Communication between electronic station and terminal connections rely on the branch network. Simulation experiment shows the test of data traffic and network delay of IP communications network. In the actual network environment the data refresh meet the application requirements. So the program on the improvement of distribution automation communication in this article is feasible.

Abstract: In power system, identification of harmonics and interharmonics has especially important role in improving power quality. In order to identify accurately the parameters of harmonics and interharmonics, a new parameters estimation method of harmonics and interharmonics, which combines TLS-ESPRIT with particle swarm optimization (PSO) algorithm, was put forward. We call it as TLS-ESPRIT-PSO algorithm in this paper. This algorithm firstly estimates number and frequency of the harmonics and interharmonics. Then, according to estimated number and frequency of the harmonics, the amplitude and phase of the harmonics and interharmonics were estimated by PSO algorithm. The experiment results prove that the TLS-ESPRIT-PSO algorithm can provide effective and accurate results in the analysis of harmonics and interharmonics. Therefore, TLS-ESPRIT-PSO algorithm is a promising identification algorithm for harmonics and interharmonics.

Abstract: In order to ensure the sustainable development of resource-exhausted cities,with Dongchuan disrict of Kunming as an example, the achievements and problems in the economic transformation, as well the relationship between the geological hazards and mining were analysed,the results showed that Dongchuan has achieved good results in the process of transformation in economy, city transformation, and ecological construction.However, the basic cause of severe natural disasters lie in over-exploitation is ignored for the misunderstanding of the causes of geological disasters.Therefore, the prominent problem in the development of transformation is the insufficient emphasis on eco-environmental protection.Resource-exhausted cities must pay attention to ecological construction in the transformation process for keeping the economic and environmental sustainability.

Abstract: This project applies Data Mining technology to the prediction of electric power system load forecast. It proposes a mining program of electric power load forecasting data based on the similarity of time series research, in the method, the average of each segment of time-sequence load is used to reduce the dimension of the problem. The similarity inquiring of each sub-sequence of loads is realized by using slipping window and MBR method. The inquiring is improved in efficiency by designing the index structure according to the-tree. Effectively overcome the negative effects on the prediction results caused by the limited and incomplete data. It also illustrates a list of examples to prove that the conducted method is effective and efficient.

Abstract: As a basic industry, the coal industry has greatly associated with the development of national economy. The coal industry has a tight association with the development of national economy. This paper calculates the direct consumption coefficient and the complete consumption coefficient among coal industry and other national economy sectors in an input-output model based on the Input-Output Tables of 2007, and analyze the reaction of each sector to coal price fluctuation. The results show that most of the top ten are industry sectors, and the sector which is the most influenced one is industry of production and supply of electric power and heat power. If the coal price rises by 10%, this sector will accordingly rise by 1.79%.