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Performance assessment of control loops is of great importance for industrial production. This paper proposes a novel performance assessment and controller tuning method for non-Gaussian MIMO feedback control systems. First, an algorithm based on minimum entropy and mutual information projection to latent structure (ME-PLS) was proposed to replace the canonical correlation analysis algorithm (CCA). The ME-PLS algorithm decomposes the system data into independent components related to inputs and outputs, and this algorithm applies to both Gaussian and non-Gaussian systems. Each pair of principal components represents a virtual non-Gaussian control loop. Next, the performance of each virtual loop is calculated separately with the non-Gaussian minimum entropy method. Finally, to identify the parameters of each virtual loop, the author gives a least absolute deviation iterative algorithm based on the CARMA model (CARMA-LADI). When the control does not work well, based on the ME-PLS algorithm’s relationship and the CARMA-LADI algorithm’s identification results can give the controller tuning direction.

This article aims to conduct an in-depth investigation into the environmental impact of Hall thruster plumes on spacecraft surface charging. The non-uniform plasma plume generated by Hall thrusters may trigger charging and discharging effects, making the assessment of surface charging risks crucial. Through numerical simulations using SPIS system, this study evaluates the surface charging characteristics of a complex spacecraft in orbit, simulating the effects of turning on and off the thrusters, as well as varying distances between the thrusters and the spacecraft. The simulation demonstrates that turning on the thrusters significantly affects spacecraft charging, reducing the potential difference between spacecraft surfaces from 3740 V to 19.2 V, effectively alleviating electrostatic discharge on the spacecraft surface. The closer the thruster is to the spacecraft, the more CEX ions are collected on the surface, influenced by the beam ions, resulting in a surface potential change of 1.3 V, with minor effects on surface potential but contributing to increased deposition contamination on the spacecraft surface.

Transportation-related emissions are the dominant contributing source of air pollutants today. Considering the negative impacts of transportation-related emissions on our social and economic environment, extensive efforts have been made by researchers and practitioners attempting to find solutions to reduce the emissions. To synthesize these research efforts, researchers have conducted various reviews of relevant studies. However, because of the diversity of the topics, most of existing reviews have only focused on specific and narrowed areas. Furthermore, none of the existing reviews have attempted to summarize the researchers' opinions on the current research and their prospects of the future research directions. Therefore, this paper is intended to fill this gap by conducting an extensive survey of transportation emissions professionals. In the paper, a review of existing research and developments on each of the emissionsrelated topics is provided, followed by a presentation of the respective survey results and analysis. At the conclusion of these reviews and the analysis of the survey, some future research directions in this field are presented. [ABSTRACT FROM AUTHOR]