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In the cold rolling process, friction coefficient, oil film thickness and other factors vary dramatically with the change in the rolling speed, which seriously affects the strip thickness deviation. This paper aims to improve the strip control precision with the forecast roll gap model based on CF-PSO-SVM approach in the rolling process.

In this paper, a novel forecasting model of the roll gap based on support vector machine (SVM) optimized by particle swarm optimization with compression factor (CF-PSO) is proposed. Based on lots of online data, the roll gap models regressed by PSO-SVM, genetic algorithm (GA)-SVM and CF-PSO-SVM are obtained and verified through evaluating the performances with the decision coefficient (R²), mean absolute error and root mean square error. In addition, with the good forecasting performances of CF-PSO-SVM, a roll gap compensation model is studied.

The results indicate that the proposed CF-PSO-SVM has excellent learning regression ability compared with other optimization algorithms. Meanwhile, a roll gap compensation model based on the rolling speed and plastic coefficient is obtained, which has been proved validated in product.

In this paper, the SVM algorithm is combined with traditional rolling technology to solve the problems in actual production, which has great supporting significance for the improvement of production efficiency.

To examine “universal service” as a policy objective in post‐WTO accession Chinese telecommunications and analyze the challenges of the Chinese telecommunications system in defining and promoting public service ethos in a country that is marked by staggering disparities.

A range of media, academic, industry, and policy discourses on “universal service” and a broader notion of “public service,” together with recent government efforts in promoting “universal service,” are examined and assessed to develop an analysis of the uneven nature of China's telecommunications development and reveal the dynamics of “universal service” policy formation, as well as the impetuses and impediments in developing any notion of public service telecommunications in China.

Public service issues in China need to be situated within a continuing process of uneven development which comprises dimensions other than residential telephone access. Although the ultimate policy goal appears to develop a nationally accessible telecommunications infrastructure as the basis of a unified national economy, this overall objective is beset by conflicts and contingent on the dynamics of elite and popular struggles over and beyond telecommunications development. Despite the spectacular expansion in telephone access, pragmatic concessions to dominant power groups, rather than a principled commitment to “universal service,” let alone efforts to define the social functions of telecommunications in more democratic ways, have shaped the development of China's telecommunications.

The development of China's telecommunications infrastructure offers lessons both as to the likelihood of successfully establishing an integrated national economy, and the role of public service in that context. However, the Chinese telecommunications policy field remains extremely fluid.