To investigate the contribution and temporal variability of lake-groundwater interactions in the water balance of flood-controlled lakes, Honghu Lake in the middle reaches of the Yangtze River was selected as a case study. Based on the analysis of water level dynamics of Honghu Lake and surrounding groundwater, the recharge-discharge relationship between Honghu Lake and groundwater were identified and calculated by a water balance equation. The contribution of groundwater-lake interactions to the water balance of Honghu Lake and its temporal variability were examined. The results indicate that there is a significant water level difference between Honghu Lake and the adjacent phreatic groundwater, with dynamic changes in both showing a significant positive correlation, correlation coefficient r=0.729. The aquifer in the Honghu Lake area is permeable, which indicates that there are interaction conditions between Honghu Lake and groundwater. On an inter-annual scale from 2017 to 2022, Honghu Lake generally infiltrate into the groundwater, with an average annual discharge volume of 6.43×10⁸ m³, accounting for 14.11% of the lake's outflow. On a multi-year average monthly scale from 2017 to 2022, Honghu Lake infiltrates into the groundwater during the dry season (September to February of the following year), with an average monthly discharge volume of 0.8×10⁸ m³. During the rainy season (April to August), groundwater-lake interactions are dynamic, with an average monthly exchange volume of -1.17×10⁸~0.88×10⁸ m³. Honghu Lake presents an opposite seasonal variation characteristic of the lake water-groundwater interaction compared with the reported Yangtze-connected lakes such as Poyang Lake and Dongting Lake. This is mainly because the water level of Honghu Lake, affected by water conservancy regulation, has altered the natural interaction process between the lake and groundwater. These findings provide new insights into groundwater-lake interactions in flood-controlled lake systems and hold significance for the management of water resources and ecological protection in the Honghu Lake region.

In order to study the structural strength of platform fire fighting vehicles, and to address the impact of the structural design of its sub-frame, stabilizers, and booms on the stability and safety of the entire vehicle, ANSYS software simulation was used to study its structural strength, and experimental verification was conducted. A simplified 3D model of the sub-frame with stabilizers, and the booms were established separately, the stress distribution under various working conditions was simulated. Then, an experimental environment was set up for stress testing. The results show that when the entire boom is horizontally extended to the left or right of the fire fighting vehicle, it is more likely to experience the phenomenon of virtual legs, with the values of 22.5 mm and 17.5 mm, respectively. The maximum stress of the boom during the retraction and extension process occurs in the area of the folding arm's variable amplitude hinge point and the overlapping area of the telescopic arm. And the difference between the stress data obtained from experiments and simulations is about 4%. This not only provides good guidance for the security testing of platform fire fighting vehicles, but also verifies the credibility of the simulation method, which is helpful for the structural design and optimization of platform fire fighting vehicles.

In order to ensure the regular and punctual operation of civil aviation transportation, the efficient aviation spare parts supply is the fundamental basis. However, the stochastic replenishment lead time and demand aggregates the uncertainty of spare parts supply. An original equipment manufacturer-orientated aviation industry supply chain location-inventory problem under an uncertain environment was investigated. A two-stage stochastic optimization model, including facility location, inventory control, production decisions, etc., was constructed to maximize the supply chain's profit. A novel robust optimization approach was proposed for a resilient supply chain network design under an uncertain environment. The results show that original equipment manufacturer facilities are more likely to establish double-sourcing and multiple-sourcing strategies with the upstream tier suppliers as the supply lead time and demand uncertainty increase and the on-hand inventory and average ordering quantity of tier suppliers increase accordingly. In addition, high uncertainty in spare parts supply and demand leads to declining profits in the aviation industry supply chain, which can be relieved by robust and resilient supply chain design and efficient inventory control. It is concluded that the optimal strategic and tactical decisions of the aviation industry supply chain in the context of supply and demand uncertainty provide an effective solution for the robust and efficient operations of the global aviation industry supply chain.

To determine the accuracy of the light hydrocarbon parameter obtained from the headspace gas, crude oils and associated gases from six wells in the western part of the Qaidam Basin were collected. The composition and carbon isotopes of individual light hydrocarbons from headspace gas and natural gas were analyzed and compared. The results show that the content of C₅—C₇ light hydrocarbons obtained from headspace gas is higher than that in natural gas, but the relative contents of each light hydrocarbon obtained from two methods are similar. It is found that light hydrocarbon parameters calculated from headspace gas and natural gas share similar results in studying the genesis type, generation temperature and other aspects, but get different results in evaluating the maturity by using heptane and isoheptane values. Besides, the carbon isotopes of individual light hydrocarbons in headspace gas are greater than those in natural gas, among which cyclo-alkanes have the smallest carbon isotope difference. Particularly, the carbon isotopes of methylcyclohexane (δ¹³C_MCC6) in the headspace gas are close to those in natural gas. Therefore, the main parameters of light hydrocarbons and δ¹³C_MCC6 can be accurately obtained from the headspace gas of crude oil. The research results provide a basis for enriching the application of light hydrocarbon geochemistry in oil and gas accumulation.

In order to solve the problems of large heat leakage and unclear stress of the adiabatic support structure in the cryogenic storage tank, a finite element model of a 37.4 m³ storage tank was established by the method of thermal-solid interaction, and the heat transfer, stress and deformation of the tank were analyzed, and the supporting structure was optimized. The results show that the daily evaporation rate of liquid nitrogen is 0.10%/d when the heat leakage through the supporting structure is 62.18 W, and the heat leakage of the supporting structure decreases with the decrease of ambient temperature. The influence of liquid temperature on the storage tank is mainly concentrated in the support structure and the inner tank, and the stress and deformation of the support structure increase greatly after considering the influence of temperature, and the maximum stress of the inner tank is less affected, and the deformation is increased by 11.81 times. When storing liquid hydrogen, the heat transfer of the support structure increases by 26% compared with liquid nitrogen. The topology of the supporting structure under the sliding end was optimized with the minimum heat transfer as the optimization goal. The heat transfer of the “Y” type support structure is reduced by 27.20% and the maximum stress is reduced by 7.73%.

In the process of coal seam mining, it is easy to cause problems such as large roof overhang area and long collapse step, which affects the failure form of the surrounding rock of the roadway and the deterioration and failure of the supporting body. In view of the occurrence of thick and hard roofs in the 113105 working face of the Bojiang Haizi Mine and the instability of the narrow coal pillars along the empty roadway, the use of roof cutting and pressure relief is an effective way to effectively solve the problem of roof overhang, and the design of its key parameters has an important impact on the pressure relief effect. In order to explore the influence of different roof cutting pressure relief heights on the roof stress evolution law above the narrow coal pillar along the empty roadway, the effect of lateral roof cutting of roadway was studied by combining theoretical analysis, numerical simulation and field observation. Based on the slip-revolve stability theory of masonry beams, the mechanical model of the roof of the coal pillar under different roof cutting heights was constructed, and the bearing stress distribution equation of the coal pillar after different roof cutting heights was obtained. FLAC3D software was used to simulate the stress distribution and displacement evolution characteristics of the coal pillar roof under different roof cutting heights. The simulation results show that the slitting surface formed after the implementation of roof cutting technology effectively blocks the stress propagation path, and the vertical stress peak value in the coal body on both sides of the roadway decreases, and the pressure relief effect gradually increases with the increase of the roof cutting height, when the roof cutting height reaches 19 m, the stress of the coal pillar roof decreases by 17.22 MPa, and the pressure relief rate is 43.4%. The displacement of the roof of the coal pillar gradually decreases with the increase of the roof cutting height, and the reduction rate gradually decreases. The field test shows that according to the designed roof cutting height, the stress of the surrounding rock is significantly reduced, and the deformation degree of the roadway meets the normal mining requirements.

In deep oil and gas development, it is difficult to drill targeted with traditional sliding drilling tools because of the increasing number of wells with complex structure. To help solve the problem of wellbore trajectory control in complex structural wells, a discontinuous directional rotary steerable structure was proposed. Moreover, a mechanical model of discontinuous directional rotary steerable bottom hole assembly(RSBHA) was established by combining the element division idea of finite element method and the continuous beam-column theory. The bit side force and dip angle of were calculated by compiling mechanics program. The effects of borehole geometry parameters, drilling parameters and drill assembly structure parameters on mechanical properties were analyzed. It is concluded that weight on bit and inclination of hole have little influence on bit side force, but the structural parameters of drill assembly have great influence. The research results provide theoretical premise for the optimization of RSBHA structure and drilling parameters, and provide mechanical support for accurate control of wellbore trajectory.

Modeling social networks using directed graphs and calculating the influence of nodes in settlement graphs using deep learning methods are important branches in the field of social research. In order to solve the problem that graph neural networks cannot well calculate the influence of nodes based on constructed node features, inspired by GraphGPS, a heat module was designed to propose a method of calculating the influence of nodes that integrated semantic, behavioral, and heat information in real networks. Firstly, the self-information obtained based on nodes' multiple centrality and orthogonal distribution sampling was used as the initial semantic features of the nodes. Secondly, the node features were fused by graph neural network. Once again, the node heat information was learned by the heat module. Finally, the fusion of the extracted semantic, behavioral, and heat features was implemented to calculate the node influence. Experiments were conducted on four real network datasets. The results show that the model with the addition of the heat module can effectively calculate node influence.

In order to study the mechanical properties of the column foot joint of a self-resetting cylindrical pier, the mechanical mechanism of self-resetting cylindrical pier column foot joint with circular section was analyzed theoretically. The calculation formula of key points of the whole force and displacement hysteresis curve of the pier was derived, including yield point, failure point, etc. The theoretical analysis model of the relationship between pier jacking force and displacement was established. Based on OpenSees platform, fiber hinge model was used to model the section of pillar foot of self-resetting energy-consuming pier. Combined with pseudo-static test results, the feasibility and accuracy of the fiber hinge model were verified. On this basis, a self-resetting cylindrical pier was set up by fiber hinge model, and the key point of the deduced force-displacement hysteresis curve was compared with the skeleton curve of the simulated cylindrical pier to verify the accuracy of the deduced method. The results show that the derivation method can obtain the pressure relief point, yield point and failure point of self-resetting cylindrical pier, which can provide reference for the research of self-resetting pier with circular section in the future.

To enhance the efficiency of carbon monoxide (CO) emission control during drill-and-blast construction in high-altitude tunnels and to improve the working environment for personnel, a tunnel currently under construction at a high altitude was investigated. Utilizing the computational fluid dynamics simulation software Fluent, three factors were examined under forced ventilation conditions: the distance between the air duct and the tunnel face, the position of the air duct, and the varying elevations. To model the diffusion characteristics of harmful CO gases. The simulation results indicate that when the air duct is positioned too close to the tunnel face, vortices form, causing CO accumulation near the tunnel face, which is detrimental to the effective dispersal of CO from this area. Conversely, when the duct is positioned too far, the airflow loses a significant amount of kinetic energy before reaching the tunnel face, which also hinders the effective removal of harmful CO gases in the vicinity of the tunnel face. Optimal removal efficiency of harmful CO gases near the tunnel face is achieved when the air duct is placed at a distance of 25.2 m from the tunnel face and located at the top of the tunnel. This configuration significantly improves the working environment for personnel within a short period. Compared to plain regions, the distance between the duct and the tunnel face in high-altitude areas should be approximately 3 \sqrt{S} (S is the cross-sectional area of the tunnel) that of the plain regions. The trend of CO movement within the tunnel is generally consistent across different altitudes. As the altitude increases, the concentration of CO also increases, and the speed of CO movement within the tunnel decreases, necessitating longer ventilation times in high-altitude areas.