Continuum robots have been widely used in natural cavity intervention therapy, but the current flexible continuum robots have poor positioning accuracy and lack of accurate navigation means. In response, a multi-segment continuum robot shape reconstruction method based on electromagnetic positioning information was proposed, aimed at achieving accurate end navigation and positioning. An efficient two-stage active structure shape reconstruction method based on third-order Bessel curve was proposed. The solution of Bessel curve was optimized to nonlinear least squares problem, which was solved quickly and accurately by particle swarm algorithm with linear decreasing weights. The proposed method can accurately fit the shape of the two-segment continuum and has good real-time performance. The results show that within the bending angle process, the average root-mean-square error of shape reconstruction is 0.48 mm, which is 0.8% of the length of the continuum bending segment. The accuracy and reliability of the proposed shape reconstruction method for intracavitary interventions using micro-continuum robots are demonstrated through detailed modeling and validation results.

1g shaking table test refers to the shaking table test carried out under conventional gravity conditions, which is the mainstream type of shaking table test at present. A distinction was made between strict similarity models and strain distortion models, primarily utilizing the control equation method with supplementary dimensional analysis. The similarity relationships between these models and the prototype during different deformation stages in rock slope 1g shaking table tests were theoretically derived, and the key parameters required to achieve similarity between the model and the prototype were established. Numerical tests were conducted to verify and evaluate the established similarity relationships for different deformation stages, considering the inherent vibration characteristics and dynamic response characteristics of rock slopes. The results indicate that both strict similarity models and strain distortion models can accurately calculate the natural vibration characteristics of the prototype slope and the dynamic response characteristics during the elastic deformation stage under seismic loads. However, for large deformation issues, it is recommended that the strain similarity ratio be close to or equal to 1. These research findings provide valuable references for the design of similarity relationships and the selection of similarity models in 1g shaking table tests for rock slopes.

In order to explore the impact of the number of bearing plates on the bearing capacity of the expanded pile and the soil around the pile, a small half face pile model test equipment developed was used to record the deformation of the soil around the pile in real-time using using digital image correlation (DIC) technology equipment, and to analyze the displacement and failure characteristics of the soil around the pile. Experimental research shows that during loading, the soil under the load-bearing plate is compressed to form a compression zone, and the influence range of this zone gradually increases with the increase of load, while squeezing towards the soil on both sides. The cracks above the bearing plate continue to develop until a free zone is formed, and this area expands with the increase of load. The bearing capacity of three plate piles has been significantly improved compared to single plate piles and two plate piles, but their load-settlement curve shapes are relatively similar. During the loading process, the displacement changes of the soil around the pile near and below the bearing plate are the most significant. Therefore, the study supplements the research on the impact of the number of bearing plates on the soil around piles and other related directions.

During growth, crop stalks are prone to bending deformation, posing challenges for computer visualization simulation. A differential analysis method was employed to investigate the physical stress-strain relationship of stalks, and a visualization simulation method was proposed for flexible stalks. Firstly, a mechanical model of the stalk under tensile, bending, shear, and torsional loads was established. Secondly, a geometric model based on a semi-structural approach and surface modeling was constructed. Finally, C++ and OpenGL were utilized to implement the visualization simulation. Experimental analysis of the bending stress-strain characteristics of stalks from different varieties was conducted. The results demonstrate that this method can relatively accurately simulate the deformation process of stalks. The physics-based model ensures the accuracy of bending simulation, providing a novel informatics analysis tool for selecting and breeding lodging-resistant crop varieties.

In order to accurately predict the water richness of the weathered bedrock aquifer, 28 groups of weathered bedrock pumping test borehole data in Zhangjimao minefield were used as training and verification samples, and the lithology combination index, weathering index, thickness, core recovery rate and burial depth of the weathered bedrock were selected as evaluation indexes. Based on whale optimization algorithm-support vector machines (WOA-SVM), a water-rich identification model for weathering bedrock aquifers was proposed. This model can predict the water-rich grade of the weathered bedrock in the area without pumping test data, and realize water-rich zoning of the weathered bedrock in the well field by comprehensive use of the geological information of 249 exploration boreholes. The study shows that the weathered bedrock of Zhangjiamao minefield is weakly water-rich as a whole, and its spatial distribution is uneven. There are strong water-rich areas in the central part of the field and the local area along Wulanbula Gully, but their distribution range is small, there are some moderately water-rich areas in the central-western and southeastern parts, and the northeastern and southwestern areas are weakly and very weakly water-rich almost all the time. The results predicted are more in line with the actual situation, and the research results can provide a reference for the safe production of the mine and a new way of thinking for the prediction of the water-richness of the weathered bedrock.

In order to efficiently and accurately predict freight forwarders’ transportation modes preferences between China and Europe during major emergencies, as well as to uncover the relevant factors influencing freight forwarders’ choices, the stated preference method was employed to survey freight forwarders. Additionally, considering the influences of transportation and cargo attributes, decision trees, logistic regressions, and random forest prediction models were constructed to forecast the selection behavior of freight forwarders. The prediction results of the machine learning model and the discrete choice model were comprehensively compared through four evaluation metrics: accuracy, precision, recall, and F₁ score. Furthermore, the random forest algorithm was utilized to rank the importance of attributes influencing freight forwarders’ transportation mode choices during different stages of the pandemic. The study results demonstrate that the prediction accuracy of all three machine learning models is higher than that of the discrete choice model. Among them, the random forest model exhibits superior prediction accuracy compared to the decision tree and logistic regression models in addressing the choice of Sino-Europe container transport modes, making it more suitable for this problem. Regarding influencing factors, during stable periods, cargo attributes are identified as the most important factors. When major emergencies occur, freight forwarders place greater emphasis on the threshold delay time. Furthermore, the destination and value of the cargo are found to have significant impacts on the choice of Sino-Europe container transport modes. The study proposes an accurate analysis of the decision-making mechanisms guiding freight forwarders’ mode choice behavior during major global emergencies. Furthermore, it is utilized by shipping companies and operators of the China Railway Express to gain a deeper understanding of the preferences and decision-making factors influencing freight forwarders. The insights derived from this study are considered a solid basis for effectively responding to similar emergency situations.

Aiming at the problem of short effective prediction time for the movement history of amphibious aircraft in waves, the statistical values of amphibious aircraft movement over a period of time were proposed to predict, and a prediction model for the statistical characteristics of amphibious aircraft movement was constructed based on long short-term memory neural networks(LSTM). Taking the NACA TN 2929 amphibious aircraft as an example, based on its numerical simulation data, the statistical values of the three degrees of freedom motion of heave, roll, and pitch of amphibious aircraft under sea conditions of level 3, 4, and 5 were predicted, and their prediction effects were analyzed in detail. The results show that the LSTM neural network-based model for predicting the statistical characteristics of amphibious aircraft motion has good prediction accuracy. In practical engineering applications, this model can accurately predict the statistical values of amphibious aircraft motion in the future, providing auxiliary decision-making information for offshore operations.

In order to study the mechanical properties of negative Poisson’s ratio(NPR) anchor cable under static tension and drop hammer impact load, the self-developed NPR anchor cable tension test system and NPR anchor cable drop hammer impact test system were used to conduct static tensile test and dynamic impact test for a certain batch of NPR anchor cables. Its resistance and absorption of slow deformation and instantaneous impact energy of surrounding rock were verified by the supporting force, elongation and expansion of anchor cable. Secondly, a 3D numerical model of NPR anchor cable was established, and relevant numerical parameters were calibrated according to laboratory test results. The static tensile test of NPR anchor cable and the drop hammer impact test were carried out. The results of the numerical test are in good agreement with those of the laboratory test, which verifies the reliability of the numerical model. The 3D numerical model of NPR anchor cable can be used as an auxiliary analysis tool for the improvement and upgrading of NPR anchor cable in the future.