10 research outputs found

    U-model-based two-degree-of-freedom internal model control of nonlinear dynamic systems

    Get PDF
    This paper proposes a U-Model-Based Two-Degree-of-Freedom Internal Model Control (UTDF-IMC) structure with strength in nonlinear dynamic inversion, and separation of tracking design and robustness design. This approach can effectively accommodate modeling error and disturbance while removing those widely used linearization techniques for nonlinear plants/processes. To assure the expansion and applications, it analyses the key properties associated with the UTDF-IMC. For initial benchmark testing, computational experiments are conducted using MATLAB/Simulink for two mismatched linear and nonlinear plants. Further tests consider an industrial system, in which the IMC of a Permanent Magnet Synchronous Motor (PMSM) is simulated to demonstrate the effectiveness of the design procedure for potential industrial applications

    Prevalence of and Risk Factors for Peripheral Neuropathy in Chinese Patients With Diabetes: A Multicenter Cross-Sectional Study

    Get PDF
    Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes, and its progression significantly worsens the patient's quality of life. This study investigated the prevalence and risk factors associated with DPN in a large sample of Beijing individuals with type 1 and 2 diabetes, as well as compared the diagnostic methods for DPN. A total of 2,048 diabetic patients from 13 centers in Beijing were assessed for DPN through questionnaires and examination. Patients were divided into DPN group and suspected DPN/non-DPN group. The demographic, clinical and biological characteristics between the two groups were compared. Binary logistic regression analysis was performed to identify potential variables associated with DPN in diabetic patients. The diagnostic methods for DPN were also compared. Among the 2,048 diabetic patients, 73 cases of type 1 diabetes mellitus, 1,975 cases of type 2 diabetes were included in this study. Among them, 714 (34.86%) were identified with DPN, 537 (26.22%) were suspected of having DPN, and 797 (38.92%) were identified without DPN. Patient's age, duration of diabetes, and diabetic retinopathy were the significant independent risk factor for DPN among patients with type 2 diabetes. The odds ratio (OR) was 1.439 (95% confidence interval (CI): 1.282–1.616, P < 0.001), 1.297 (95% CI: 1.151–1.462, P < 0.001), and 0.637 (95% CI: 0.506–0.802, P < 0.001), respectively. Ankle reflex, temperature sensation plus vibration sensation are the best screening test for patients with type 1 and 2 diabetes. The Youden indexes were 62.2 and 69.8%, respectively. The prevalence rates of DPN in the Chinese patients with type 1 and type 2 diabetes in Beijing were 21.92 and 35.34%, respectively. Patient's age, duration of diabetes, and diabetic retinopathy are the independent risk factors for DPN

    Adaptive fixed-time neural networks control for pure-feedback non-affine nonlinear systems with state constraints

    Get PDF
    A new fixed-time adaptive neural network control strategy is designed for pure-feedback non-affine nonlinear systems with state constraints according to the feedback signal of the error system. Based on the adaptive backstepping technology, the Lyapunov function is designed for each subsystem. The neural network is used to identify the unknown parameters of the system in a fixed-time, and the designed control strategy makes the output signal of the system track the expected signal in a fixed-time. Through the stability analysis, it is proved that the tracking error converges in a fixed-time, and the design of the upper bound of the setting time of the error system only needs to modify the parameters and adaptive law of the controlled system controller, which does not depend on the initial conditions

    Morphometric Assessment for Functional Evaluation of Coronary Stenosis with Optical Coherence Tomography and the Optical Flow Ratio in a Vessel with Single Stenosis

    No full text
    Objectives: The study aimed to evaluate the diagnostic performance of optical coherence tomography (OCT) in identifying functionally significant coronary stenosis in a vessel with single stenosis. Background: The OCT-based morphofunctional computational method for deriving the optical flow ratio (OFR) has diagnostic value, as it can identify the functional severity of coronary stenosis, but the ability of the OFR to aid the OCT in determining coronary stenosis hemodynamics in single-stenosis lesion remains unclear. Methods: 74 vessels with single stenosis were studied in 69 patients; all cases were performed through OCT and quantitative flow ratio (QFR), and OCT images were used to perform OFR. Results: Among vessels with single stenosis, OFR showed a good correlation with QFR (r = 0.86; p p p 2 and 1.40 mm. Conclusions: OFR has a good correlation with QFR. OCT-measured MLA and MLD have excellent diagnostic efficiency in identifying the hemodynamic significance of coronary stenosis in a vessel with single stenosis

    A multi-center randomized prospective study on the treatment of infant bronchiolitis with interferon α1b nebulization.

    No full text
    BACKGROUND:The respiratory syncytial virus (RSV) is the main cause of bronchiolitis in infants and interferon (IFN) α is a commercial antiviral drug. The nebulization of IFN α1b could be a viable treatment method. In this study, the therapeutic effects and safety of IFN α1b delivery via nebulization in infant bronchiolitis were investigated in this multi-center prospective study. METHODS AND FINDINGS:Bronchiolitis patients admitted to 22 hospitals who met the inclusion criteria were enrolled and randomly allocated to four groups: control, IFN Intramuscular Injection, IFN Nebulization 1 (1 μg/kg), and IFN Nebulization 2 (2 μg/kg) groups. All patients were observed for 7 days. The therapeutic effects and safety of different IFN delivery doses and delivery modes were evaluated. Coughing severity change, as scored by the researchers and parents, between days 1 and 3 was significantly different between the IFN Nebulization 2 and control groups. Lowell wheezing score change between days 3 and 5 was significantly different between IFN Nebulization 1 and control groups. There were no significant differences among the four groups regarding the number of consecutive days with fever, three-concave sign, fatigue and sleepiness, and loss of appetite. There were no cases of severe complications, no recurrence of fever, and no regression of mental status. CONCLUSIONS:IFN-α1b could more effectively alleviate coughing and wheezing in bronchiolitis. IFN-α1b nebulization had significant advantages in shortening the duration of wheezing and alleviating coughing
    corecore