Search

Underwater acoustic sensors are vital for monitoring marine environments and detecting targets, but their optimal placement presents challenges, particularly in deep-sea environments. This paper addresses the question of determining the optimal sensor placement in a specific ocean region through a principled optimization approach. While previous studies mainly utilized heuristic algorithms without exploiting problem-specific structures, this work explores leveraging the complex three-dimensional acoustic environment through principled modeling and tailored optimization. Specifically, intricate three-dimensional multi-directional acoustic maps are constructed for each sensor. Based on these maps, the sensor placement problem is then cast as an integer linear programming, allowing the study to leverage established theoretical results from operations research. Additionally, an alternative algorithm with its performance indicator is presented to find near-optimal solutions efficiently and can empirically reach over 99% coverage of the optimal solution. Experimental results using real-life data from the South China Sea demonstrate the effectiveness of the proposed approach in achieving much larger detection coverage compared to random and empirical strategies. Notably, the alternative fast algorithm approaches the optimal solution in significantly less time. Furthermore, experiments show that any further simplification of this approach leads to the performance degradation. [ABSTRACT FROM AUTHOR]

Abstract\nIMPLICATIONS FOR REHABILITATIONAim: Physical exercise is essential for the physical and mental health of visually impaired people, but they often face challenges such as inaccurate movements, lack of rhythm and difficulty in mastering postures during exercise. This project introduces an assistive device based on a multi-channel interaction design strategy to improve the accuracy of yoga practice for the visually impaired and to enable their independent exercise.Methods: The system uses a 1:1 model combined with an output interaction model. The effectiveness was verified through controlled experiments with unassisted exercise as the control group and yoga-assisted exercise as the experimental group. Improvements in yoga accuracy and product usability were verified using the Assisted Accuracy Scale and the SUS Scale, respectively.Results: The results showed that the multi-channel interaction design significantly improved the accuracy and usability of yoga exercises and enhanced the ability of visually impaired people to exercise independently.Conclusion: Through this project, we hope to replicate this design strategy to help more visually impaired individuals independently perform effective physical exercise at home, in a gym, or in an outdoor space, thereby improving their quality of life and overall health.A yoga assistive device called E-YOGA, which improves the accuracy of yoga for the visually impaired through augmented interactive technology, thereby enhancing the ability of the visually impaired to exercise on their own.By participating in sports activities, visually impaired people can improve their health, living ability, body system and organ function.Regular physical activity is essential for visually impaired people, not only to build strength and endurance, but also for simple daily activities that require a lot of energy.A yoga assistive device called E-YOGA, which improves the accuracy of yoga for the visually impaired through augmented interactive technology, thereby enhancing the ability of the visually impaired to exercise on their own.By participating in sports activities, visually impaired people can improve their health, living ability, body system and organ function.Regular physical activity is essential for visually impaired people, not only to build strength and endurance, but also for simple daily activities that require a lot of energy. [ABSTRACT FROM AUTHOR]

In order to explore the stability change law of the south slope during the process of the inner dumping pressure foot in the south open pit coal mine in Xinjiang, this paper studied the dynamic change law of the slope stability during the process of the inner dumping pressure foot in the south open pit coal mine by means of numerical simulation and theoretical analysis. Firstly, the FLAC3D strength reduction method was used to simulate the process of the inner dumping pressure foot in the south slope, and the variation rule of the potential sliding surface position and stability coefficient in the process of the inner dumping pressure foot in the south slope was obtained. The optimal geometrical parameters of material cross section in the south side of the southern open-pit mine are obtained. Based on the numerical simulation results, the limit equilibrium theoretical model of the inner dumping pressure foot in the south slope was established, and the calculation formula of the stability coefficient of the middle south wall in the process of the inner dumping pressure foot was deduced. The evolution law of slope stress in the process of pressing foot in the south slope is expounded and the mechanism of the change of the position of the potential slip surface and the improvement of the stability of the middle south wall in the process of the inner dumping pressure foot was expounded.

As the number of traffic accident casualties continues to rise globally, this study aims to enhance traffic safety during highway emergency repairs. Based on the fundamentals of human vision, this study designed a novel interactive barricade design, R-barricade, which aims to improve the visibility and warning effect of the barricade, as well as to enhance the interaction with the operator in order to reduce the risk of accidents. We established a comprehensive visual criteria framework, combined with eye-tracking technology, to systematically evaluate the R-barricade. The evaluation results show that the design effectively improves the driver's attention to the barricade and effectively extends the gaze time, significantly improves the reaction time, and effectively improves the safety of the barricade. This study provides new perspectives for evaluating and improving traffic safety measures during highway emergency repairs and contributes scientific support to the advancement of interactive transport systems and road safety management. [ABSTRACT FROM AUTHOR]

Herein, we investigate the temperature compensation for a dual-mass MEMS gyroscope. After introducing and simulating the dual-mass MEMS gyroscope's working modes, we propose a hybrid algorithm for temperature compensation relying on improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN), sample entropy, time–frequency peak filtering, non-dominated sorting genetic algorithm-II (NSGA II) and extreme learning machine. Firstly, we use ICEEMDAN to decompose the gyroscope's output signal, and then we use sample entropy to classify the decomposed signals. For noise segments and mixed segments with different levels of noise, we use time–frequency peak filtering with different window lengths to achieve a trade-off between noise removal and signal retention. For the feature segment with temperature drift, we build a compensation model using extreme learning machine. To improve the compensation accuracy, NSGA II is used to optimize extreme learning machine, with the prediction error and the 2-norm of the output-layer connection weight as the optimization objectives. Enormous simulation experiments prove the excellent performance of our proposed scheme, which can achieve trade-offs in signal decomposition, classification, denoising and compensation. The improvement in the compensated gyroscope's output signal is analyzed based on Allen variance; its angle random walk is decreased from 0.531076°/h/√Hz to 6.65894 × 10−3°/h/√Hz and its bias stability is decreased from 32.7364°/h to 0.259247°/h. [ABSTRACT FROM AUTHOR]

In this study, secondary metabolites of Eurotium cristatum were isolated and purified by high-speed counter-current chromatography (HSCCC), and their hypoglycemic activities were studied. The general-useful estimate of solvent systems (GUESS) for counter-current chromatography was employed to select the appropriate solvent systems of n-hexane-ethyl acetate-methanol-water (HEMW, 4:6:5:5, v/v/v/v) for HSCCC practice, and three compounds were separated from the crude ethyl acetate extract of E. cristatum in one single step; 6.1 mg of Compounds 1, 5.6 mg of Compound 2 and 3.8 mg of Compound 3 were obtained from 100 mg of crude extract with a stationary phase retention of 75%. The compounds were then identified as emodin methyl ether, chrysophanol and emodin, respectively. The activity of the target compounds in the secondary metabolites of E. cristatum was verified by testing their inhibition on α-glucosidase activity and molecular docking simulation. The results showed that emodin, chrysophanol and emodin methyl ether had significant inhibitory effects on the α-glucosidase activity. This work confirmed the effectiveness of HSCCC in the separation of compounds in complex extracts and provided reference for further research and application of E. cristatum. [ABSTRACT FROM AUTHOR]