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This paper investigates the problem of robust output feedback control tracking for a class of nonlinear dual-rate sample-data systems subject to time-varying disturbances. These dual-rate systems, known as slow measurement fast control (SMFC) systems, are characterised by a slow sampling rate of the sensor and a fast updating rate of the controller. To facilitate high-frequency signal tracking, this paper introduces an alternating predictive generalised proportional integral observer (APGPIO). The proposed control method not only effectively restores the system state and captures disturbance changes between samples but also enhances the control bandwidth and anti-disturbance ability, enabling effective tracking of high-frequency reference outputs. By combining it with a fast updating sample-data feedback controller, APGPIO utilises predictive methods to increase the sampling rate of the system's sensors, matching the update frequency of the controller. Stability analysis demonstrates that the tracking error of this hybrid nonlinear system converges to a bounded region centred at the origin. Finally, the designed method's high control bandwidth and anti-disturbance ability are demonstrated through multiple sets of simulations using a real system. [ABSTRACT FROM AUTHOR]

The aim of this meta-analysis was to compare sleep outcomes of AS patients and controls. Six electronic databases were searched: PubMed, Embase, IndMed, Cochrane Library, CNKI and Web of Science. Statistical analyses were executed using Revman 5.3 software. Nine studies and a total of 3169 participants were included in the meta-analysis. When sleep was assessed using PSQI, significant differences were observed in subjective sleep quality, sleep latency, sleep efficiency, sleep disorders, sleep medication use and total PSQI between patients with AS and controls, and subjective sleep quality was most severely affected. In PSG, eight variables of sleep quality (stage I sleep, stage II sleep, slow wave sleep, rapid eye movement, arousal index, periodic leg movement index, sleep latency, sleep efficiency) were lower in AS patients than in controls. Three variables of sleep quality assessed by USI (estimated sleep time, sleep sufficiency index, number of awakenings per night) and two variables of sleep quality assessed by MOS sleep scale (sleep disturbance scale, sleep problem index II) were lower in AS patients than in controls. It indicated that AS patients experience more serious sleep disorders. Early recognition and appropriate interventions are essential to improve patients' sleep quality. [ABSTRACT FROM AUTHOR]