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The signal of small defects in steel wire rope is often submerged in wave noise. Therefore, it is difficult to detect small defects in wire rope and easy to miss detection. In order to solve this problem, a steel wire rope defect magnetic flux leakage detection method based on improved complementary ensemble empirical mode decomposition (ICEEMD) is proposed. To avoid the influence of the lubricant or dust on the surface of the wire rope on the detection signal, the electromagnetic detection method is adopted. CEEMD-WTF-WF multi-stage noise reduction method is obtained by combining ICEEMD, wavelet threshold filtering (WTF) and Wiener filtering (WF). The intrinsic mode function (IMF) component is obtained by decomposing the magnetic flux leakage signal of steel wire rope through ICEEMD. The energy ratio, permutation entropy and cross-correlation coefficient of IMF components are calculated. The IMF trend component and IMF stock noise component are extracted. WTF is conducted on the stock noise component to filter the useful IMF component reconstruction signal. WF is applied to the reconstructed signal to remove random noise. The eigenvalues of the de-noised defects are extracted, input and trained by BP neural network. The magnetic flux leakage signals of the steel wire rope defects are identified. The experimental results show that ICEEMD-WTF-WF multi-stage noise reduction method has good noise reduction effect on the magnetic flux leakage signal of steel wire rope. The SNR and kurtosis indexes are better than those of WTF, moving average filter and WF. The BP neural network model based on ICEEMD-WTF-WF takes a short time to detect. The average accuracy rate of small defects reaches 98.13%, which can better meet the requirements of wire rope defect detection.

Metaheuristic algorithms are widely used in engineering problems due to their high efficiency and simplicity. However, engineering challenges often involve multiple control variables, which present significant obstacles for metaheuristic algorithms. The Crested Porcupine Optimizer (CPO) is a metaheuristic algorithm designed to address engineering problems, but it faces issues such as falling into a local optimum. To address these limitations, this article proposes three new strategies: composite Cauchy mutation strategy, adaptive dynamic adjustment strategy, and population mutation strategy. The three proposed strategies are then introduced into CPO to enhance its optimization capabilities. On three well-known test suites, the improved CPO (CAPCPO) outperforms 11 metaheuristic algorithms. Finally, comparative experiments on seven real-world engineering optimization problems demonstrate the advantages and potential of CAPCPO in solving complex problems. The multifaceted experimental results indicate that CAPCPO consistently achieves superior solutions in most cases. [ABSTRACT FROM AUTHOR]

Aiming at the problems of faults, precipitation, weak layers and other factors inducing the deformation and instability of the end slope of the open-pit mine, taking the north slope of Dongming Open-pit Mine as the engineering practice background, the method of combining numerical simulation theory and limit equilibrium analysis is used. The influence of the weak layer of the north side slope on the deformation and displacement law of the slope rock and soil, and at the same time, combined with the limit equilibrium analysis method to control the stability of the north side slope, two schemes are proposed, namely, slope cutting and load reduction + pressure reduction. Through analysis and research, and based on the calculation results of Geo-slope and engineering geological conditions, the plan of slope cutting and load reduction + presser foot is finally adopted, which provides a reference for safe and efficient production during actual mining.

Aiming at the problem that the attitude sensor of the quadrotor was susceptible to interference, resulting in large attitude output errors, a multi-sensor quadrotor attitude control system based on STM32 was designed. The system used sensors such as MPU6050 to collect the attitude data of the quadrotor in real time, calculated the attitude through the quaternion complementary filtering algorithm, and used the cascade PID control to drive the motors in PWM mode. Based on the design of the software and hardware of the system, the physical production and flight test of the quadrotor were completed. The results show that the system can flexibly control the attitude of the quadrotor UAV and realize the stable flight of the quadrotor UAV.

The reform of property right system of natural resources is the only way to promote the construction of ecological civilization in China. By systematically combing the construction process of China’s natural resources assets property rights system and drawing lessons from foreign property rights system experience, this paper can systematically analyze the main problems faced by China’s natural resources assets system at present, and put forward targeted policy suggestions for reform.