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Electro-hydraulic actuators offer advantages over traditional hydraulic actuators, particularly for high-precision force or position control, but their nonlinear dynamics complicate modelling and control. This study proposes a predictor-integrated adaptive controller to address these challenges. By combining a proportional-integral-derivative controller with a sliding surface, the system tracks desired trajectories, while a parameter optimization rule minimizes errors. Additionally, a smart grey prediction model with dynamic step size adjusts parameters and generates control signals to reduce noise and disturbances. Simulations show improved accuracy and control performance, with a root mean square error reduction of over 50% compared to traditional control algorithms. This adaptive approach ensures precise control in varying conditions, making it suitable for aerospace, automotive, and robotics applications.

The aim of this study was to recover bioactive compounds from Smallanthus sonchifolius roots, including flavonoids, terpenoids, phenolics, vitamin C, and reducing sugar contents, as well as to examine antioxidant activities using ultrasonic-assisted and microwave-assisted extraction technique. Single-factor experiments were employed to explore the impact of various independent variables, including concentration, extraction method, power, duration, temperature, and pH, on the dependent variables of yacon extraction using the ultrasonic-microwave-assisted extraction method. The Plackett-Burman Design Model was used to screen the parameters that significantly influenced the extraction efficiency. Box-Behnken Design Model was utilized to optimize the ultrasonic-microwave-assisted extracting process to acquire bioactive compounds. The highest yield of total flavonoid contents was obtained with 4.00 of pH, 743.33 W of microwave power, and 39.08°C of ultrasonic temperature. According to reducing sugar contents yield optimization, the optimum conditions were 3.98 of pH, 36.17 seconds of microwave time and 40°C of ultrasonic temperature. To optimize vitamin C concentration, the optimized conditions were 1:40 g/mL of sample-to-solvent ratio, 3.99 of pH, 45.33 seconds of microwave time, and 451.09 W of ultrasonic power. Regarding total terpenoids yield, optimized conditions for extracting were 1:40 g/mL of sample-to-solvent ratio, 2.48 of pH, 30.49 seconds of microwave time, and 49.48 °C of ultrasonic temperature. Under optimized conditions, the recovery yield of flavonoid, terpenoid, vitamin C, and reducing sugar contents were 7.95 mg rutin equivalents/g, 47.93 mg ursolic acid equivalents/g, 107.78 mg ascorbic acid/g, and 230.39 mg D-glucose equivalents/g, respectively. Ultrasonic-microwave-assisted extraction showed significantly higher performance than singular extracting methods and is regarded as a sustainable and effective approach to recover target compounds from yacon roots.

This investigation focused on assessing and enhancing ultrasound-assisted extraction (UAE) using natural deep eutectic solvents (NADES) to extract phenolics and terpenoids from sweet basil leaves. The initial stage involved evaluating the extraction performance of twelve NADES and ethanol. A NADES comprising lactic acid and glucose with a 2 : 1 molar ratio and 20% water content (WC) obtained the highest total phenolic content (TPC) and total terpenoid content (TTC). Single-factor experiments systematically examined the impact of liquid-to-solid ratio (LSR), water content in NADES (WC), ultrasound power, temperature, and exposure time on the extraction yield. Optimization using Box–Behnken Design (BBD) models for the lactic acid and glucose-based UAE revealed the optimal conditions to be 80 ml/g LSR, 30% water, 300 W, 50°C temperature, and a 15-minute exposure time. Under these optimized parameters, the extraction achieved the highest TPC and TTC at 69.88 mg GAE/g and 110.71 mg UA/g, respectively. This study presents an environmentally friendly and sustainable extraction protocol for the extraction of phenolic compounds and terpenoids from sweet basil leaves.

ABSTRACTSThis study extracted flavonoids and phenolics from watermelon fruit by microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) combined with a natural deep eutectic solvent (NADES). The effectiveness of NADES combined with UAE and MAE was evaluated for extracting these compounds from watermelon rinds. The study chose a 2:1 molar ratio of hydrogen bond donors (HBDs) to hydrogen bond acceptors (HBAs). Among the tested combinations, 1,2-propanediol-lactic acid showed the highest solubility for flavonoids and phenolics within the extraction system. Experiments with a single factor were used to examine the effects of different parameters on total phenolic content (TPC) and total flavonoid content (TFC). The Box-Behnken design (BBD) model optimized the NADES-based UAE and MAE processes based on TPC and TFC responses. The results of the experiment and the predicted values from the BBD agreed well. Optimal conditions for recovering phenolics and flavonoids from watermelon rinds with NADES-based UAE were determined as 1/60 g/ml for SLR, 300 W, 20% water content, and 15 min, while NADES-based MAE: 1/50 g/ml for SLR, 400 W, and 3 min. This study presents an efficient approach for extracting biologically active compounds from watermelon. [ABSTRACT FROM AUTHOR]

A characterization of near-field impulse responses based on electromagnetic (EM) near-field data from an EM solver to explore features of the propagation process on a well-known wideband traveling wave antenna—double-slot Vivaldi antenna—is presented in this article. The intensity, propagating time and partitional response characteristics facilitate interpretation of the propagation process and impacts of the antenna partitions on the process. The EM energy flows guided, reoriented and scattered along a sequence of antennas transmitting and radiating segments were recognized. The geometric features of near-field wavefront surfaces supported evaluation of the EM flow proportions and antenna directivity. Impact of the structural section on radiation was also assessed by the partitional far-field response characteristic in frequency and time domains. Supported by many complementary characteristics in the analyses, inherent features of the propagation process were emphasized and false flags were minimized. By this approach, the simplification for the near-field propagation model contributed to enhancing the insight of near-field propagation processes on the double-slot antipodal Vivaldi antennas and enabled optimizing the antenna structure details. [ABSTRACT FROM AUTHOR]

The aging in higher education in the post-COVID-19 context has created many disparities in development, particularly affecting vulnerable groups. This article analyzes the aging situation in higher education and the challenges posed by the post-pandemic era. It proposes solutions, including various policy adjustments and changes specifically related to higher education, to build a stronger workforce and society in the future. These efforts aim to address population aging and improve the quality of education. National policies need to be tailored to the specific circumstances of each country, ensuring fairness and effectiveness in the recovery process.

Dự báo ngắn hạn sản lượng điện năng điện mặt trời mái nhà là công cụ thiết yếu trong quá trình vận hành hệ thống điện một cách hiệu quả. Bài báo này trình bày khảo sát về dự báo ngắn hạn sản lượng điện năng của một hệ thống điện năng lượng mặt trời sử dụng các mạng neuron nhân tạo. Dữ liệu được thu thập từ hệ thống giám sát với công suất điện và bức xạ mặt trời từ ngày 21/04/2022 đến 01/6/2022. Bốn mô hình mạng neuron được sử dụng để dự báo điện năng gồm: mạng neuron lan truyền thẳng nhiều lớp (MLFF), mô hình neuron tự hồi quy phi tuyến tính với đa biến ngoại sinh (NARX), mô hình neuron bộ nhớ dài-ngắn hạn (LSTM) và mô hình kết hợp NARX-LSTM. Các phương pháp đề xuất để kiểm tra hiệu quả cho các bài toán dự báo 5 phút và 1 giờ. Kết quả cho thấy mô hình mạng neuron truyền thẳng nhiều lớp cho kết quả dự báo chính xác hơn so với các phương pháp khác trong cả 2 trường hợp tính toán.