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The aim of this paper is to investigate the synergism effect between lanthanum salt (La(NO₃)₃) and benzotriazole (BTAH) on the corrosion inhibition of commercial brass and to further study the inhibition mechanism.

Potentiodynamic polarization curves were carried out on bare brass and brass treated with additions of optimum concentration of BTAH, La salt and La salt+BTAH to the basal deposition solutions in 3.5 wt. percent sodium chloride solution. The inhibition mechanism of the composite conversion coatings on brass obtained in optimal deposition techniques were investigated by electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), X‐ray diffraction (XRD), and FT‐IR reflection spectra.

A “Critical La(NO₃)₃ content” and “Critical BTAH content” were both observed, at which the coatings prepared performs the highest protectiveness, and La(NO₃)₃ and BTAH had an excellent synergism effect on the corrosion inhibition of brass. The corrosion mechanisms for uncoated and coated brass are different. A remarkable enhancement of the brass's corrosion protection was obtained by the formation of composite conversion coatings consisted of Cu(I)BTA and La coordinate thing except for Cu₂O and La₂O₃, which acted as a barrier avoiding the release of metal ions and inhibited the diffusion of the oxygen.

The results from this paper showed that La(NO₃)₃ and BTAH could be used together to prepare the novel composited conversion coatings on commercial brass for the good corrosion inhibition.

The purpose of this paper is to recover the waste heat of flue gas heat exchanger (FGHE) as efficiently as possible and avoid the acid dew corrosion of that.

A novel flue gas waste heat recovery system was proposed in the paper. The dynamic mathematical models of key equipment in that were established based on theory and experiment method. The proportion integration differentiation-differentiation (PID-P) cascade control method based on particle swarm optimization algorithm was used to control the outlet temperature of FGHE. The dynamic characteristics of the flue gas heat exchange system were simulated by the particle swarm optimization algorithm with different fitness functions.

The PID-P temperature controller parameters can be quickly and effectively obtained by the particle swarm optimization algorithm based on the fitness function of integral time absolute error (ITAE). The overshoot, rise time and adjusting time of the novel system are 2, 83 and 105s, respectively. Compared with the traditional two-step tuning (T-ST) method, the novel system is better in dynamic and steady-state performance. The overshoot and the adjustment time of the system are reduced by 44% and 328s, respectively. ITAE is a performance evaluation index for control system with good engineering practicability and selectivity.

The dynamic mathematical model of key equipment in the new flue gas waste heat recovery system is established and the system's control strategies and methods are explored.

Visual tracking technology enables industrial robots interacting with human beings intelligently. However, due to the complexity of the tracking problem, the accuracy of visual target tracking still has great space for improvement. This paper aims to propose an accurate visual target tracking method based on standard hedging and feature fusion.

For this study, the authors first learn the discriminative information between targets and similar objects in the histogram of oriented gradients by feature optimization method, and then use standard hedging algorithms to dynamically balance the weights between different feature optimization components. Moreover, they penalize the filter coefficients by incorporating spatial regularization coefficient and extend the Kernelized Correlation Filter for robust tracking. Finally, a model update mechanism to improve the effectiveness of the tracking is proposed.

Extensive experimental results demonstrate the superior performance of the proposed method comparing to the state-of-the-art tracking methods.

Improvements to existing visual target tracking algorithms are achieved through feature fusion and standard hedging algorithms to further improve the tracking accuracy of robots on targets in reality.

Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a method that can use two-dimensional contours obtained from the image for the three-dimensional dental mesh model restoration.

First, intra-oral image and smiling image are taken from the patient, then teeth shapes of the images are designed based on esthetic restoration concepts and the pixel coordinates of the teeth’s contours are converted into the vertex coordinates in the three-dimensional space. Second, the dental mesh model is divided into three parts – active part, passive part and fixed part – based on the teeth’s contours of the mesh model. Third, the vertices from the teeth’s contours of the dental model are matched with ones from the intra-oral image and with the help of matching operation, the target coordinates of each vertex in the active part can be calculated. Finally, the Laplacian-based deformation algorithm and mesh smoothing algorithm are performed.

Benefitting from the proposed method, the dental mesh model with esthetic restoration can be quickly obtained based on the intra-oral image that is the result of doctor-patient communication. Experimental results show that the quality of restoration meets clinical needs, and the typical time cost of the method is approximately one second. So the method is both time-saving and user-friendly.

The method provides the possibility to design personalized dental esthetic restoration solutions rapidly.