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Objective: To investigate the correlation between ultrasonic measurements of swallowing movement parameters and aggravation of swallowing dysfunction in patients with chronic obstructive pulmonary disease (COPD). Methods: COPD patients with swallowing dysfunction (n = 120) and COPD patients with normal swallowing function (n = 100) treated in our hospital between January 2020 and January 2023 were included in observation and control groups, respectively. The correlation between ultrasonic measurements of swallowing movement parameters and COPD with swallowing dysfunction was analyzed. The observation group was divided into mild and severe groups according to their Gugging Swallowing Screen (GUSS) scores. The correlation between ultrasonic measurements of swallowing movement parameters and COPD exacerbation combined with swallowing dysfunction was analyzed. Results: In the observation group, Hyoid muscle thickness, hyoid bone displacement, geniohyoid muscle movement distance, HLAS, and CSR were lower compared to the control group, negatively associated with COPD‐related swallowing issues. Conversely, geniohyoid muscle movement time and minimum hyohyoid distance (NHLA) were higher in the observation group, positively correlated with COPD‐related swallowing dysfunction. In COPD patients with swallowing problems, the severe group exhibited lower values for lingual muscle thickness, hyoid bone displacement, geniohyoid muscle movement distance, HLAS, and CSR compared to the mild group, while geniohyoid muscle movement time and NHLA were higher in the severe group. Receiver operating characteristic (ROC) curves were created, indicating the promising diagnostic utility of these parameters for assessing the presence and severity of swallowing dysfunction in COPD patients. Conclusion: The ultrasonic measurement of swallowing motion parameters can effectively assess swallowing dysfunction in COPD patients. [ABSTRACT FROM AUTHOR]

With the fast proliferation of microgrids integrated into the power grid, several nearby microgrids with common benefit have been coupled to be multi‐microgrids (MMGs), which is a significant stage for developing the smart grid. A suitable control structure and corresponding control device need to be proposed for the MMGs operating efficiently. However, mostly micrgrid control devices are still restricted to the single microgrid and have limited application without the common design. The authors develop control devices with a prodigious popularisation value for the MMGs based on the hierarchical control structure. According to the proposed four‐layer control architecture (scheduling layer, central control layer, integrated terminal layer and bottom layer), the hardware and software design suitable for the MMGs control devices and its multi‐time scale communication architecture has been presented. Furthermore, the appearance design and interface exploitation were introduced as well. Experimental results are provided to demonstrate the validity of the proposed MMGs control structure and devices, which could contribute to the large‐scale application of MMGs control devices and provide a reference for other MMGs projects. [ABSTRACT FROM AUTHOR]

The V/f control adopted by the master power supply has problems of slow dynamic response, poor anti‐interference ability in response to micro‐source output power fluctuations and loads abrupt change. Aiming at problems of the output voltage mentioned above, an improved V/f control strategy based on compound control is proposed in this study. The improved V/f control strategy is composed of two parts, feedforward compensation and robust feedback control. The design of the feedforward compensator is realised by the method of approximate full compensation. The design of the robust feedback controller is transformed into solving a convex optimisation problem with linear matrix inequality constraints and linear objective functions. The designed V/f control strategy is verified by a variety of comparative tests. Test comparisons show that the controller can get better voltage output characteristics, dynamic characteristics and robustness in response to micro‐source output power fluctuations, loads abrupt change or non‐linear loads and unbalanced loads. [ABSTRACT FROM AUTHOR]