As global cities, Hong Kong, Shanghai and Beijing operate in international economic networks; however, they are also each firmly embedded within a regional context and are surrounded by less populous and less internationally recognized neighbors. Together they form so-called mega-city regions referred to as the Greater Pearl River Delta, the Yangtze River Delta, and the Bohai Rim, each encompassing a dozen or so cities. In the wake of staggering economic growth and threatening pollution, these cities are compelled to respond to the challenge of ecological modernization (EM): aim for higher economic value added at lower environmental cost. Cities have particular industrial and regional profiles; consequently they follow different developmental pathways. In order to attract coveted investors, green and high-tech corporations, well-endowed residents and talented workforce, these cities engage in city branding practices. In this contribution, a typology of EM developmental pathways is presented and the 41 cities in the three Chinese mega-city regions are analyzed in terms of their respective pathways and city branding practices. We argue that different industrial and regional profiles allow for different developmental pathways making different city branding strategies likely. Most cities brand themselves in comformity with what their pathway would lead us to predict, except cities with a strongly manufacturing oriented profile; the brands of the latter type deviate markedly from their current reality. Cities adopting branding strategies that contrast sharply with their historical legacy and current profile risk promoting themselves in ways that the outside world is likely to perceive as lacking in credibility.@en

Due to its simple mechanical structure and high motion stability, the H-shaped platform has been increasingly widely used in precision measuring, numerical control machining and semiconductor packaging equipment, etc. The H-shaped platform is normally driven by multiple (three) permanent magnet synchronous linear motors. The main challenges for H-shaped platform-control include synchronous control between the two linear motors in the Y direction as well as total positioning error of the platform mover, a combination of position deviation in X and Y directions. To deal with the above challenges, this paper proposes a control strategy based on the inverse system method through state feedback and dynamic decoupling of the thrust force. First, mechanical dynamics equations have been deduced through the analysis of system coupling based on the platform structure. Second, the mathematical model of the linear motors and the relevant coordinate transformation between dq-axis currents and ABC-phase currents are analyzed. Third, after the main concept of inverse system method being explained, the inverse system model of the platform control system has been designed after defining relevant system variables. Inverse system model compensates the original nonlinear coupled system into pseudo-linear decoupled linear system, for which typical linear control methods, like PID, can be adopted to control the system. The simulation model of the control system is built in MATLAB/Simulink and the simulation result shows that the designed control system has both small synchronous deviation and small total trajectory tracking error. Furthermore, the control program has been run on NI controller for both fixed-loop-time and free-loop-time modes, and the test result shows that the average loop computation time needed is rather small, which makes it suitable for real industrial applications. Overall, it proves that the proposed new control strategy can be used in industrial applications that have high-precision and high real-time performance requirements@en

In the semiconductor industry, positioning accuracy and acceleration are critical parameters. To improve the acceleration speed of a motor, this paper proposes the moving-coil maglev planar motor with a concentric winding structure. The coordinate system has been built for the multiple degrees of freedom movement system. The Lorenz force method has been applied to solve its electromagnetic model. The real-time solving of the generalized inverse matrix of factors can realize the decoupling of the winding current. When the maglev height changes, the electromagnetic force and torque decreases exponentially with the increase of the air gap. To decrease the influence on control system performance by the internal model change and the external disturbance, this paper proposes an improved active disturbance rejection control (ADRC) to design the controller. This new controller overcomes the jitter phenomenon due to the turning point for the traditional ADRC, thus it is more suitable for the maglev control system. The comparison between ADRC and the improved ADRC has been conducted, the result of which shows the improved ADRC has greater robustness.

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