With the acceleration of the transition to new energy systems, it is urgent to carry out in-depth research on the complex energy characteristics of multi-load users. A technology of constructing user energy characteristic label library and a user portrait method were proposed, which comprehensively considered the coupling characteristics of electric, cold and thermal multiple loads. Firstly, the high redundancy and low correlation features were eliminated by the fast correlation filtering algorithm, and the features with strong distinguishing ability were selected by the random forest and recursive feature elimination algorithm. In the clustering stage, the improved three-way adaptive density peak clustering (3W-ADPC) algorithm improved the load clustering effect by combining the adaptive neighbor search and the three-branch clustering algorithm. The empirical results show that the proposed method has dual advantages in computational efficiency and clustering accuracy, and can accurately reveal the comprehensive energy use characteristics and deep information of multi-load users, which confirms the practical value of the proposed method in the study of multi-load users’ behavior.

Compared to image instance segmentation in general scenes, instance segmentation in complex stacked scenes is affected by complex situations such as severe occlusion and stacking of similar objects, making instance segmentation more difficult. To solve the problem of garbage instance segmentation in complex stacking scenarios, an instance segmentation algorithm combining YOLOv8 and two-layer feature network strategy was proposed. Firstly, the feature data was layered in the data preprocessing part, and the two-branch feature fusion was realized through the graph convolutions network (GCN), which reduces the influence of stacking on the features of the occluded objects, thus solving the instance segmentation problem under complex stack occlusion. At the same time, in order to solve the problem that similar objects are easily confused, a soft threshold non-maximum suppression algorithm and a new intersection ratio algorithm were integrated. Finally, according to the complexity of application scenarios and data sets, the feature extraction module of the backbone network was optimized, and the multi-scale attention mechanism was introduced in the backbone network, which effectively improves the detection performance of the model. In the experiment, examples of occlusive garbage classification were used to segment the dataset. The experimental results show that this method outperforms other methods in terms of average accuracy, average accuracy when the intersection to union ratio threshold is 0.5 (AP₅₀), and average accuracy when the intersection to union ratio is 0.5~0.95 (AP_50~95). Compared with the original YOLOv8 algorithm, the detection AP₅₀is increased by 7.9% and the segmentation AP₅₀ is increased by 5.4%, which has better detection and segmentation effects.

The construction of the shield tunnel for the high-speed railway will impact the settlement of railway tracks, roadbeds, and other structures, potentially affecting the railway’s operation. In order to study the influence of shield tunnel underneath the high-speed railroad in Guiyang area on the settlement pattern of frame box culvert, roadbed and high-speed railway track and the shield construction parameters suitable for Guiyang area, relying on Guiyang Rail Transit Line 3, the model of soil layer-frame culvert-roadbed-track was established to analyze the settlement law of shield construction in limestone on frame culvert, existing high-speed railroad track and roadbed, and to optimize the parameters of shield construction. The results indicate that the settlement of the frame culvert exhibits a “W” shaped transverse and longitudinal settlement pattern, with a peak settlement value of 1.805 mm during the tunneling process. The shield machine’s crossing causes a sudden change in subgrade settlement, with the peak value reaching 1.753 mm. High-speed rail track settlement shows a single peak with excavation, with a peak value of 1.41 mm. Analysis of eight types of shield tunneling pressure and grouting pressure reveals that grouting pressure has a better control effect on settlement than excavation pressure. Increasing grouting pressure leads to a decrease in the peak value of subgrade surface settlement, with the peak value reaching 1.355 mm at 800 kPa grouting pressure. The maximum deformation rate is 20.7%, with grouting pressure set at 800 kPa and tunneling pressure at 100 kPa for the shield machine.

The drainage consolidation characteristics of municipal sludge are closely related to its water occurrence form. However, there is insufficient understanding of the water transformation law of municipal sludge after chemical conditioning and consolidation. Based on the theory of soil science, the soil-water potential curves of different types of municipal sludge were tested by centrifuge method, and the water forms of municipal sludge were divided into bound water, capillary water and gravitational water according to the range of soil-water potential. On this basis, the different forms of water content in the original sludge, consolidated samples and conditioned sludge samples were compared to reveal the water transformation law of municipal sludge under the action of consolidation and chemical conditioning. The results show that the bound water content of the sludge is reduced by 70%~80% and the free water content is doubled after the sludge is modified by ionic salt. Under the consolidation pressure of 3.1 kPa, only a part of gravity water is discharged from different types of municipal sludge, and the contents of capillary water and bound water are basically unchanged. Under the consolidation pressure of 100 kPa, the gravity water is completely discharged, the capillary water is significantly reduced, and the bound water is slightly reduced.

The low-load one-time construction method of PVC micro-pipe jacking was applied in China and is in its infancy. The small stiffness of the flexible PVC pipe ring leads to the redistribution of soil pressure and the generation of elastic resistance during the jacking process. The jacking force can not be accurately calculated by the existing specifications. The principle and construction method of the PVC micro-pipe jacking method were used to investigate. At the same time, the influence of vertical deformation of PVC pipe on soil arching effect and the additional frictional resistance caused by horizontal deformation were considered based on Terzaghi soil pressure. The corresponding jacking force calculation formula was derived on this basis. Furthermore, the factors that influence the jacking force of PVC pipes were analyzed through finite element numerical simulation. The results indicate that the pressure around the PVC pipe will increase due to the deformation of the pipe. The maximum error between the predicted lower limit and the measured value of the jacking force calculation model proposed is 15%. The measured value is between the predicted upper limit and the lower limit, which proves its applicability. The parametric analysis indicates that the jacking force increases by 1.6 times as the pipe diameter increases by 100 mm and the jacking force increases by about 3 times when the buried depth of the pipeline increases from 4.5 m to 6 m.

Aiming at the problem of time-consuming and labor-intensive routing path design in the cable layout design of complex electromechanical products, an automatic routing technology for complex electromechanical product cables based on multi rules particle swarm algorithm was proposed. Firstly, the cable routing environment of electromechanical products was analyzed, and the routing path was abstracted into a sequence of points to complete the definition of cable routing space. Through pose transformation, the problem of difficult interference detection between wiring paths and parts in electromechanical products was solved. In order to make full use of the wiring space, the particle multiple rules were introduced into the particle swarm optimization algorithm. By using particle number, multi-scale collision detection, adjacent waypoint replacement method and fourth-order quasi-uniform B-spline curve method, the problem that the routing environment is complicated and the optimal solution cannot be obtained was solved, and the searching ability, solving speed and routing quality of the algorithm were improved. Through simulation analysis and comparison with other algorithms, the superiority of the algorithm is proved. The example proves that the proposed method can search feasible paths efficiently during routing. The generated routing paths do not interfere with parts in three-dimensional space, and there are no mutation points in the path fairing, which provides a new idea for the automatic routing of complex electromechanical products.

Aiming at the problems of anti-noise, anti-high resistance and complex threshold setting of traditional pole selection methods, a fault selection method of flexible DC distribution line based on Res-BiLSTM network was proposed. Firstly, the original fault signal was subjected to complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), and then the reconstructed signal was obtained by using the correlation coefficient and Shannon entropy for reconstruction. Secondly, the Res-BiLSTM network model was constructed for the pole selection. In order to improve the network accuracy and the convergence speed, the channel attention module was introduced into the split-attention network. The reconstructed signal features were extracted using the convolutional bidirectional long short-term memory and the improved split-attention network at the same time. The extracted features were fused using the attention feature fusion module, and the fused features are classified. Finally, PSCAD/EMTDC was employed to construct the model and to verify the proposed methodology. The simulation results show that the proposed pole selection method is highly accurate, anti-interference, and independent of fault distance.

In September 5, 2022, a M6.8 earthquake occurred in Luding County Sichuan Province. Quite a lot of store-front type buildings damaged or collapsed. Five representative buildings representing both positive and negative aspects were selected to analyze the earthquake damage mechanism through theoretical basis and model experiment. The results show that the earthquake damage is mainly concentrated in the bottom layer, which is composed of concrete column and masonry wall. The masonry wall with no lateral openings restrains the transverse and torsional deformation of the structure, and the floor only transports along the longitudinal direction, and the seismic shear force shared by each member is proportional to its longitudinal lateral stiffness. The rigid and brittle members with large stiffness will appear “internal force condensation”, and then reach “deformation saturation”, and lose the load-bearing capacity in the way of brittle failure, and the gravity of the upper layers will be borne by the transverse wall. If the earthquake does not stop at this time, the transverse wall will lose the role of “buttress” in the direction of exit plane, and the whole structure will collapse along the longitudinal contact with the ground. On the contrary, if the structure of the bottom layer avoids large differences in stiffness, it can significantly improve the seismic resistance.

In image inpainting, it is crucial that the identification and inpainting of local detail features and the preservation of global features. The models based on fractional-order partial differential equations were characterized by rich evolutionary behaviors, which allow image details to be effectively understood and a certain sharpening effect to be exhibited in image inpainting. However, issues such as inaccurate identification of large-scale features and over-sharpening are prone to be encountered. An optimal control model was proposed and the objective function was defined by the total variation energy of image global features and the constraint was formulated by a spatial fractional-order vector-valued Cahn-Hilliard equation, aiming to achieve a balanced effect between local detail restoration and preservation of global features. L₂ gradient flow, H^-1 gradient flow, and convex splitting were applied to design a numerical scheme for non-convex constraint conditions. And then the split bregman method was used to optimize the objective function with a dynamic grayscale adjustment strategy was introduced to maintain grayscale discrimination capability while enhancing computational efficiency. The numerical experiments demonstrate that the new model achieves an improvement on peak signal to noise ratio(PSNR) ranging from 0.371 8 dB to 9.935 2 dB compared to other methods, exhibiting strong competitiveness in terms of structural similarity(SSIM) and greater effectiveness on images with fragmental damages. Moreover, compared to traditional fractional-order equation models, the computational time is reduced by a factor of 49.50% to 52.91%.

A numerical calculation model for airfoil dynamic stall numerical simulation was established by computational fluid dynamics method, and the influence of plunging motion on airfoil unsteady aerodynamic force was analyzed. The simulation results were compared to the pitching motion wind tunnel experimental data of NACA0012 airfoil, and the results of the model under mild stall and deep stall conditions were in good agreement with the experimental values, which verified the accuracy and feasibility of the numerical calculation model. The plunging motion of NACA23012 airfoil was equivalent to the pitching motion, the lift characteristics of airfoil under the two motion modes are very close, but the moment characteristics are obviously different. With the increase of amplitude of plunging motion and inflow Mach number, the difference of moment characteristics is further expanded. With the increase of amplitude of plunging motion, the damping effect of aerodynamic moment of pitching and plunging motions is obviously enhanced, with the increase of inflow Mach number, the damping effect is reduced, and the moment divergence occurs when the Mach number is 0.85.