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In recent years, as the structure of smart substation network changes, the prediction of high-quality network traffic becomes more and more important. Once the traffic is abnormal, it will affect the reliability and real-time relay protection device. In this paper, the wavelet transform and BP neural network algorithm are combined to construct and analyze the wavelet neural network model. Based on this, the improved particle swarm algorithm is used to replace the gradient descent training method of wavelet neural network to improve the wavelet neural network Easy to fall into the plight of the minimum, improve the convergence rate. Finally, taking the network traffic data of station-level switch in a smart substation as an example, the simulation is carried out based on the collected original frequency data. The experimental simulation shows that the improved particle swarm optimization wavelet neural network model prediction accuracy and convergence rate is better than the traditional model, thereby improving the accuracy and speed of smart substation network traffic forecasting.

With the further smart grid, the research and application of network security situation awareness (NSSA) in smart substations are receiving more attention. In this paper, we propose a method of network safety forecasting for smart substations based on Gibbs-LDA and least square support vector machines. The project extracts all kinds of message information of intelligent substation network as message set, obtains sample characteristics and message set model, and establishes multi-dimensional prediction model of intelligent substation network security based on LDA. And use the least square support vector algorithm to get the prediction result. The experiment on the data set collected by smart substation shows that the method in this paper has the advantages of high prediction accuracy and short prediction time compared with other methods.

We demonstrated a dense sub-carrier uniform division labeling transmission system by using MATLAB software. The simulation results indicated that dense sub-carrier uniform division labeling has a good advantage over that ordinary OFDM system, and the signals at a bit rate 50Gbit/s have a good performance which is more than 10 when OSNR is equal to 25dB over 1000km optical fiber channel which only concerns the influence of polarization-mode dispersion.

OBJECTIVES—To compare background and process variables, as well as follow up status, of the participants in the International Quit and Win '96 contests of China and Finland, and analyse factors contributing to sustained maintenance. DESIGN—A standardised 12 month follow up was conducted in both countries with random samples of participants. The sample sizes were 3119 in China and 1448 in Finland, with response rates of 91.2% and 65.2%, respectively. INTERVENTIONS—The International Quit and Win '96 contest was the second coordinated, multinational smoking cessation campaign targeted at adult daily smokers. Altogether 25 countries participated, including China with 15 000 and Finland with 6000 smokers registered. MAIN OUTCOME MEASURES—Conservative (considering all non-respondents relapsed) and non-conservative (based on respondents only) estimates were calculated for one month abstinence, 12 month continuous abstinence, and point abstinence at the time point of follow up. RESULTS—Great differences were found in the background and process variables, as well as in the outcome measures. At one year follow up, the conservative continuous abstinence rates show that the Chinese participants maintained their abstinence better (38%) compared to the Finnish ones (12%). In China women reached higher abstinence rate (50%) than men (36%), whereas in Finland men achieved a better result (14%) than women (9%). CONCLUSIONS—The Quit and Win contest is a mass smoking cessation method feasible in countries showing great variance in smoking habits and rates. However, in countries with different stages of anti-smoking development, such as China and Finland, different practical implementation strategies may be needed. Keywords: smoking cessation; Quit and Win; China; Finland