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This work aims to clarify the photocatalytic degradation mechanism and heat reflectance recovery performance of waterborne acrylic polymer/ZnO nanocomposite coating. To fabricate the nanocomposite coating, ZnO nanoparticles (nano‐ZnO) were dispersed into acrylic polymer matrix at the various concentrations from 1 to 6% (by total weight of resin solids). The photocatalytic degradation of nanocomposite coating under ultraviolet (UV) light irradiation has been investigated by monitoring its weight loss and chemical/microstructural/morphological changes. As the topcoat layer, its heat reflectance recovery has been evaluated under UV/condensation exposure by using an artificial dirty mixture of 85 wt% nanoclay, 10 wt% silica particles (1–5 μm), 1 wt% carbon black, and 2 wt% engine oil. After 108‐cycle UV/condensation exposure, infrared spectra and weight loss analysis indicated that the maximal degradation for nanocomposite coating is observed at 1 wt% nano‐ZnO. On the other hand, after 96 hr of UV light exposure, the nanocomposite coating with1 wt% nano‐ZnO could restore effectively the reflective index of solar‐heat reflectance coating (from 58.45 to 80.78%). Finally, the photodegradation mechanism of this waterborne acrylic polymer coating has been proposed as the UV‐induced formation of CCCO conjugated double bonds. As a result, its self‐cleaning phenomenon can be achieved as the recovery of heat reflectance.

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The objective of this paper is to present a Predictive Torque Control (PTC) algorithm for controlling system composed by two Permanent Magnet Synchronous Motors (PMSM) operating in parallel, fed by a single power inverter. In this system, it is expected that both motors will get the same speed even if they have different conditions of load torque. The principle of PTC algorithm is considered as follows: a model of the system is used to predict the system behavior under a set of configurations of a power inverter, a cost function is built from the predicted values and their references and an optimal algorithm will be solved to find the best configuration to apply to the system in the next time step. Simulation results in Matlab/Simulink indicated that the algorithm (PTC) is well adapted for the synchronism of this system over a wide range of operations.