It is of great significance for accurate forecasting of multi-load to be carried out to improve the consumption of new energy, realize energy saving and emission reduction, and ensure the safe and reliable operation of the power grid. To enhance the accuracy of simultaneous multi-load forecasting,a model which singular spectrum analysis and bi-directional long short-term memory networks SSA-BiLSTM (singular spectrum analysis-bidirectional long short-term memory) was proposed. First, A approach Pearson correlation coefficients for coupled feature extraction was proposed to identify correlations and dependencies within multivariate load data. Then, SSA was employed for feature extraction to capture dynamic characteristics and reduced forecasting complexity. Finally, a multi-ask learning framework was introduced to leverage shared information among multiple forecasting tasks, improving prediction accuracy. Experimental using datasets from multi-area electricity, heat, cold multivariate loads, flexible and wind-solar power generation, the effectiveness of the model. The results show that the proposed model average improves in mean absolute percentage error (MAPE) for the prediction of electrical, heating, and cooling loads in multiple regions is 0.41%, with an average root mean square error (RMSE) increase of 0.02 MW.

In order to explore the strengthening effect of reinforced concrete beams strengthened by carbon fiber reinforced polymer reinforced geopolymer matrix (FRGM), the mechanical properties of reinforced concrete beams reinforced with flexural reinforcement reinforced concrete in FRGM system were studied by numerical simulation. Three-dimensional finite element models were established to simulate the failure mode, characteristic load and load-mid-span deflection curve of reinforced concrete beams reinforced by FRGM system, and the influence of the thickness and length of the FRGM layer and the pre-damage degree of the original specimen on the reinforcement effect was discussed. The results show that the thickness of the FRGM layer has no obvious effect on the ultimate bearing capacity of reinforced concrete beam, and the increase range is 72.29%~79.38%, but the stiffness of the FRGM layer is improved to a certain extent, up to 38%. The ultimate bearing capacity of reinforced concrete beams can be increased by increasing the length of the FRGM layer, but with the increase of the length of the FRGM layer, the increase of the ultimate bearing capacity gradually weakens, indicating that there is no linear increase relationship between the length of the FRGM layer and the ultimate bearing capacity. Compared with the original components, the bearing capacity of reinforced concrete beam members is improved to a certain extent after pre-damage reinforcement(36.5%~73.66%), which shows the effectiveness of FRGM reinforcement method.

To address the issues of low path planning efficiency, poor obstacle avoidance capability, and low path quality of the RRT-Connect algorithm in complex environments, an improved RRT-Connect algorithm was proposed. Firstly, a bidirectional goal bias strategy was introduced to enhance the goal-directedness and path planning efficiency of the algorithm. Secondly, an obstacle avoidance optimization strategy was proposed to increase the algorithm's active obstacle avoidance capability and passage ability in complex environments. Finally, a path recombination strategy and a smoothing strategy were added to optimize the generated initial path, reducing path length and the number of turns, and improving path quality. The improved algorithm was compared with other algorithms in three complex environments using MATLAB. Simulation results show that the improved algorithm has less planning time, shorter path length, fewer sampling times, and a higher success rate of path planning, demonstrating the effectiveness of the improved algorithm in complex environments.

In order to explore the impact of altitude on the emergency evacuation of aircraft passengers at airports, a simulation model for emergency evacuation of aircraft accidents at airports was built. By introducing panic factor, age factor, gender factor and altitude correction factor, passenger walking speed at different altitudes was quantitatively characterized, and passenger evacuation effects were analyzed under conditions such as different altitudes, with or without evacuation guidance, and cabin aisle spacing, dual aircraft evacuation. The results show that the impact of emergency evacuation time in a high plateau environment is mainly reflected in the middle and late stages of cabin evacuation and ground evacuation. When the altitude is 4 280 m, the cabin evacuation time is increased by 19.6 s and the overall evacuation time is increased by 44.1 s compared with the plain area. By setting cabin crew guidance, cabin evacuation time is reduced by 18.1 s and evacuation efficiency is increased by 16.5%. When the width of aisle spacing is increased to 60 cm, the evacuation time in the cabin is reduced by 20.8 s, and the evacuation efficiency is increased by 19%. Compared with single-aircraft evacuation, the evacuation time of dual-aircraft evacuation is significantly increased, so it is necessary to optimize the evacuation strategy. The research results can provide theoretical support for the optimization of aircraft emergency evacuation schemes at high plateau airport.

Hydrogen-injected into natural gas for pipeline transportation is an effective way to solve the high cost of hydrogen transportation. The rapid and uniform mixing of hydrogen and natural gas is an unavoidable problem to ensure the safety of hydrogen-blended natural gas pipeline transportation. Because the mixed gas flows back to the mixing pipe through the reflux pipe, it can continue to mix with the hydrogen-blended natural gas after entering, and improve the mixing uniformity. Therefore, a reflux mixer was used to mix hydrogen and natural gas. The effects of the inclination angle, diameter ratio and number of reflux pipes on the mixing properties of reflux mixers were analyzed by CFD. The results show that the reflux mixer has low pressure loss, high mixing uniformity and high reflux rate. When the inclination angle of reflux pipe, the diameter ratio of reflux pipe and the number of reflux pipe are 10°, 0.5 and 3, the reflux mixer achieves the best effect, and its pressure loss, mixing uniformity and the reflux rate are 76 Pa, 99.7% and 44.5%, respectively. The research results can provide reference for the parameters design and mixing performance of hydrogen-blended natural gas mixer.

CLT(cross-laminated timber) shear wall structure has emerged as one of the rapidly advancing mid-to-high-rise timber structural systems in recent years. Extensive research on the lateral resistance performance of CLT shear walls has been conducted by both domestic and international scholars. A comprehensive synthesis of findings concerning lateral resistance capabilities was conducted for CLT shear walls, including single-panel, multi-panel, and CLT shear walls with openings. Failure modes, load-bearing capacities, and stiffness characteristics were systematically examined across these structural variations. Comparative evaluations of multiple calculation methods for lateral bearing capacity and stiffness determination were performed, alongside a compilation of standardized methodologies from domestic and international specifications for timber shear wall analysis. Specialized recommendations were formulated specifically for CLT structural applications. Current research advancements were consolidated, and strategic directions were proposed to guide subsequent investigations into CLT shear wall performance under lateral loading conditions, establishing critical references for ongoing research development in this specialized engineering field.

Hydrogen energy is a promising secondary low-carbon energy source in the 21st century of global energy transition. However, HE hydrogen embrittlement in metallic materials refers to the diffusion of hydrogen into the metal in different forms, either in solid solution or as hydrides, causing severe lattice distortion, reducing ductility and toughness, and leading to embrittlement and fracture. It has raised a number of safety issues and limited the service life of hydrogen storage systems due to its insidious nature, abruptness, and diverse failures. In recent years, scholars have been conducting extensive research on hydrogen embrittlement, benefiting from improved experimental tests and numerical simulation methods. A comprehensive review of the latest advancements in hydrogen embrittlement research was provided: elucidating the concept of hydrogen embrittlement and the prevailing mechanism, analyzing the characteristics and factors influencing hydrogen embrittlement in storage vessels, and summarizing the characteristics and primary application scopes of the existing macro to micro, static and dynamic experimental methods in the evaluation of material hydrogen embrittlement. Special attention is given to the research progress in combining these methods with numerical simulation analyses, including their applicability and limitations in practical engineering. Insights and references might be offered to the ongoing development of evaluation methodologies for the hydrogen embrittlement resistance of metal materials.

In order to analyze the design parameters and technology adaptability of multi-stage temporary plugging and fracturing in the Triassic Chang-6 reservoir of a block in Suijing Oilfield. Based on the geological and engineering design data of the block, the influencing factors of multi-stage temporary plugging and fracturing were quantitatively analyzed in terms of reservoir characteristics, technology parameters, and construction effect. The combined weighting method was used to determine the weights of each parameter, and the ridge-type membership function was used to determine the membership degree of each factor. Based on the principles of fuzzy transformation and maximum membership degree, a fuzzy comprehensive evaluation model for multi-stage temporary plugging and fracturing was established. This model transforms the traditional single-index qualitative development effect evaluation into multi-factor quantitative evaluation. The model was applied to evaluate and analyze the Triassic Chang-6 reservoir in a block of Suijing Oilfield. The results show that this evaluation model results have an adaptation rate of 89.13% when compared to the actual effect data in the field, which can effectively evaluate the effectiveness of the implementation of temporary plugging and fracturing measures in the oil wells of the study area. The evaluation system can provide valuable references for the next implementation of temporary plugging and fracturing measures in the study area, and even optimize parameters for multi-stage temporary plugging and fracturing transformation in similar reservoirs.

In order to study the development law of pile top cumulative displacement of ring wing single pile foundation under horizontal cyclic load, a three-dimensional numerical model of the interaction between ring wing single pile and saturated clay was established through secondary development using ABAQUS, and also simulated the process of soil stiffness attenuation. Numerical results indicate that installing gravity type ring wings at the mud surface position of traditional single pile foundations can enhance the overall horizontal resistance of the ring wing single pile foundation, thereby reducing the cumulative displacement of the ring wing single pile under cyclic loads. The displacement of the pile top will decrease with the increase of the height and diameter of the gravity type ring wing, but increasing the diameter of the gravity type ring wing has a more significant effect on reducing the horizontal displacement of the pile top. Increasing the depth of the pile into the soil can significantly reduce the cumulative displacement at the top of a single circular wing pile under cyclic loading.

Accurately and in real-time understanding the changes in the scope and species communities of intertidal wetlands is an important foundation for achieving sustainable development and management of wetland intertidal zones. In recent years, global warming, rising sea levels, and human activities such as coastal development, reclamation, and aquaculture have caused serious damage to the intertidal zone. At present, there is a lack of systematic research on the classification of mangrove tidal flats in the intertidal zone of Guangxi. In order to achieve large-scale and high-precision extraction of intertidal resources in Guangxi, this article was based on GEE (Google Earth Engine) platform, using Landsat series image data of Guangxi coastal zone from 2012 to 2022, and threshold segmentation processing of the images. The various remote sensing features under the influence of tidal dynamic inundation were analyzed, and the intertidal zone range of coastal wetlands in Guangxi was extracted. Achieved the classification of tidal flats and water bodies, mangrove vegetation, and non-mangrove vegetation in the study area, with areas of 5 641.67 hm², 1 625.29 hm², and 2 156.04 hm² respectively. The overall classification accuracy reached 93.3%, with a Kappa coefficient of 0.9.