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Based on the robust control theory, aiming at the pneumatic servo elastictiy problem of flexible missile, this paper carries out the control system research. By establishing the missile rigid-elastic coupling full parameter uncertainty model, the μ-synthesis robust control system is designed based on the traditional three-loop control structure. Frequency domain analysis shows that the designed control system has strong robustness and is enough to deal with the strong uncertainty of flexible missile. Time domain simulation results show that, comparing with the classical PID control system, the μ-synthesis robust control system ensures the time-domain index, the first-order vibration amplitude of the missile body is reduced to 10%, and the attenuation time is shortened to about 0.5 s, which effectively suppresses the elastic vibration of the missile.

In order to improve the pointing accuracy of roll-pitch semi-strapdown photo-electricity stabilized platform, a method for error modeling and parameter calibration of stabilized platform is proposed. Based on the mechanical structure characteristics of the roll-pitch seeker, the main error sources of the stabilized platform are analyzed. Established the linear error model of the misalignment angle by using the coordinate transformation method and Taylor formula, and designed a method to improve the line-of-sight measurement accuracy of the stable platform by compensating the misalignment angle error. The least square method is used to design the calibration method of error parameters. The simulation results show that the error parameter calibration method can effectively calibrate the error parameters, and the method of compensating the misalignment angle error through the misalignment angle linear error model can significantly improve the line of sight pointing measurement accuracy of the stabilized platform.

Background and Aim: Helicobacter pylori infection is linked to various gastrointestinal conditions, such as chronic active gastritis, peptic ulcers, and gastric cancer. Traditional treatment options encounter difficulties due to antibiotic resistance and adverse effects. Therefore, the aim of this study was to explore the effectiveness of a new treatment plan that combines vonoprazan (VPZ), amoxicillin, and bismuth for the eradication of H. pylori., Methods: A total of 600 patients infected with H. pylori were recruited for this multicenter randomized controlled trial. Patients treated for H. pylori elimination were randomly assigned at a 1:1 ratio to receive 14 days of vonoprazan-based triple therapy (vonoprazan + amoxicillin + bismuth, group A) or standard quadruple therapy (esomeprazole + clarithromycin + amoxicillin + bismuth, group B). Compliance and adverse effects were tracked through daily medication and side effect records. All patients underwent a 13C/14C-urea breath test 4 weeks after treatment completion., Results: Intention-to-treat (ITT) and per-protocol (PP) analyses revealed no substantial differences in H. pylori eradication rates between groups A and B (ITT: 83.7% vs 83.2%; PP: 90.9% vs 89.7%). However, significant differences were observed in the assessment of side effects (13.7% vs 28.6%, P < 0.001). Specifically, group A had significantly fewer "bitter mouths" than group B did (3.7% vs 16.2%, P < 0.001)., Conclusion: Triple therapy comprising vonoprazan (20 mg), amoxicillin (750 mg), and bismuth potassium citrate (220 mg) achieved a PP eradication rate ≥90%, paralleling standard quadruple therapy, and had fewer adverse events and lower costs (¥306.8 vs ¥645.8) for treatment-naive patients., (© 2024 The Author(s). Journal of Gastroenterology and Hepatology published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)