Search

This paper proposes a prescribed performance control policy for spacecraft attitude tracking control. The designed controller employs a kind of performance envelope function that can configure the convergence rate arbitrarily. Moreover, the controller design is based on the barrier Lyapunov function and indirect adaptive methods, which can suppress the fluctuation of external disturbances to obtain lower steady-state errors. Compared to prior studies on spacecraft attitude tracking, the proposed policy can arbitrarily configure the system convergence performance to achieve performance trade-offs in different scenarios. Moreover, the barrier Lyapunov function design and adaptive methods can achieve low steady-state errors with low computational resource consumption. Simulations that verify its effectiveness and superiority are provided herein. [ABSTRACT FROM AUTHOR]

As industrial processes grow increasingly complex, fault identification becomes challenging, and even minor errors can significantly impact both productivity and system safety. Fault detection and diagnosis (FDD) has emerged as a crucial strategy for maintaining system reliability and safety through condition monitoring and abnormality recovery to manage this challenge. Statistical-based FDD methods that rely on large-scale process data and their features have been developed for detecting faults. This paper overviews recent investigations and developments in statistical-based FDD methods, focusing on probabilistic models. The theoretical background of these models is presented, including Bayesian learning and maximum likelihood. We then discuss various techniques and methodologies, e.g., probabilistic principal component analysis (PPCA), probabilistic partial least squares (PPLS), probabilistic independent component analysis (PICA), probabilistic canonical correlation analysis (PCCA), and probabilistic Fisher discriminant analysis (PFDA). Several test statistics are analyzed to evaluate the discussed methods. In industrial processes, these methods require complex matrix operation and cost computational load. Finally, we discuss the current challenges and future trends in FDD. [ABSTRACT FROM AUTHOR]

This document is a special issue of the journal "Symmetry" that focuses on recent progress in robot control systems. The issue contains fifteen papers covering various aspects of robot control, including robotics navigation and control, aircraft/spacecraft systems, and reliable designs. The papers discuss topics such as LiDAR-GPS/IMU calibration for autonomous driving, emotion recognition in human-computer interaction, and control strategies for spacecraft and aircraft. The issue also highlights other recent studies in spacecraft robot control, control of switching systems, self-learning control, state estimation of robotic systems, and trends in control systems for micro gyroscopes. The authors of the document are Chengxi Zhang, Jin Wu, and Chong Li. [Extracted from the article]

Purpose: Tingli Dazao Xiefei Decoction (TDXD) is a Traditional Chinese Medicine (TCM) formula used to treat acute lung injury (ALI). However, the precise mechanism of TDXD in treating ALI remains unclear. We investigated the therapeutic mechanism of TDXD against ALI using a complementary approach combining network pharmacology, molecular docking, and in vitro and in vivo experiments.Material and Methods: Potential drug targets of TDXD and relevant target genes associated with ALI were retrieved from Chinese medicines and disease genes databases. Bioinformatics technology was employed to screen potential active ingredients and core targets. Validation experiments were conducted using a lipopolysaccharide (LPS)-induced ALI mouse (C57BL/6J) model, LPS-induced inflammatory RAW264.7 cells, and molecular docking between active compounds of TDXD and potential targets.Results: Network pharmacology suggested that the mechanism of TDXD against ALI involved phosphoinositide 3-kinase (PI3K) / protein kinase B (AKT) / phosphatase and tensin homolog (PTEN) and Janus kinase 2 (JAK2) / signal transducer and activator of transcription 3 (STAT3) pathways. Quercetin, β-sitosterol, kaempferol, isorhamnetin, and L-stepholidine were identified as the main active compounds of TDXD that exerted anti-ALI effects. Molecular docking indicated that these compounds exhibited good binding capabilities (≤ − 5kcal/mol) to key targets in PI3K/AKT/PTEN and JAK2/STAT3 signaling pathways. In the animal model, TDXD alleviated injuries and inflammatory responses in lung tissues, accompanied by inhibition of expression of tumor necrosis factor-α (TNF-α), Interleukin-6 (IL-6), STAT3, and Suppressor of Cytokine Signaling 3 (SOCS3) mRNA, and key proteins in PI3K/AKT/PTEN and JAK2/STAT3 pathways (all P values < 0.05). Cell based experiments showed that TDXD dose-dependently inhibited the expression of essential proteins in PI3K/AKT/PTEN and JAK2/STAT3 pathways (P < 0.05).Conclusion: This study revealed that the mechanism of TDXD in ALI treatment might involve simultaneous regulation of PI3K/AKT/PTEN and JAK2/STAT3 pathways. [ABSTRACT FROM AUTHOR]