In order to meet the large number of future unmanned aerial vehicle (UAV) operation requirements, the safe takeoff interval for UAVs was formulated on the basis of conforming to the safety target level and aiming at the highest efficiency. According to the operating speed error characteristics of UAVs, taking into account the operating characteristics of the climb phase and cruise phase, the takeoff safety problems in three scenarios of same route operation, cross route operation and route network operation were analyzed, a collision risk assessment model was established respectively, and a calibration method for the takeoff interval was proposed in combination with Monte Carlo simulation. Finally, taking the actual operation of logistics UAVs as an example, the 10^-7 maximum collision probability was taken as the target safety level for verification, and the minimum safe takeoff interval in the three operation scenarios was analyzed and determined. The results show that the safe takeoff interval of the same route T is 122 s, the safe takeoff interval T of the cross route is related to the difference D between the distance of two takeoff points from the intersection point and satisfies T = (D±1 199.97)/14(T≥0), and the safe takeoff intervals between the four takeoff points of the airway network system are 158, 86, 0, and 0 s, respectively. The method can provide a reference for the UAV operation enterprises to carry out takeoff interval management.

Subsidence monitoring and reservoir parameters inversion in gas field can provide important supporting information for safe production protection and mining planning. The SBAS-InSAR method was used to investigate the surface subsidence evolution characteristics of Sebei gas fields from February 2022 to September 2023. Furthermore, the InSAR monitoring results were used as the observation measurements to invert the reservoir center projection coordinates, depth, strike and other parameters of the gas fields through the Prolate spheroid source. The results show that the subsidence funnel occurs in the Tainan gas field, the Sebei No.1 gas field and the Sebei No.2 gas field, and the average annual subsidence rate is -124~-109, -275~-34, and -329~-89 mm/a, respectively. Among them, the Sebei No.1 gas field and the Sebei No.2 gas field show a more significant surface subsidence phenomenon. And the surface of all three gas fields continues to sink rapidly. Further, the reservoir parameters were obtained by inversion of InSAR monitoring results. The results show that there is little difference between the deformation derived by using the optimal parameters and the observed deformation, and the spatial distribution is consistent, which indicates that it is feasible to invert the reservoir parameters of Sebei gas fields based on SBAS-InSAR deformation results.

The occurrence characteristics and genetic models of geothermal resources is an important basis for the development of geothermal resources. Drilling data, geophysical and geochemical data was applied to analyze the thermal reservoir, cap rock, heat sources, channels and supply elements, and the genetic model of geothermal system in the southwest of Zhoukou Depression was established. The development prospect was also evaluated. The geothermal resources in study area can be divided into sedimentation basin type with low temperature. Mantle derived heat is the main heat source, and the geothermal flow in the north part is higher than that in the south part, also in the protruding area is higher than that in the depressed area, reaching over 70 mW/m². The average geothermal gradient is about 2.8 ℃/hm, dominated by heat conduction system. Isotope analysis shows that the supply source comes from atmospheric precipitation in the western low mountains and hills, which infiltrates through the exposed area and moves along permeable strata and unconformity towards the east, and is heated and warmed up. The pores of the Neogene and Paleogene sandstones, as well as the karst pores of the Cambrian-Ordovician carbonate rocks, are the main storage spaces for fluids. The silt and clay deposits developed in the upper part of the Quaternary and Neogene systems form a good waterproof and thermal insulation cover layer. The development and utilization risk of the Neogene system is the lowest, with a floor depth of 400~1 400 m, increasing towards the north. The average sand to soil ratio is 40.9%, with a water flow between 40~60 m³/h and a wellhead temperature of 43~48 ℃. The development of faults also promotes the upwelling of deep heat flow, and there is a local thermal convection warming effect. Finally, four favorable development area for porous geothermal resources and three favorable areas for karst resources were identified.

In view of the current situation of unclear understanding of the genesis of the low resistivity oil layer in Guantao Formation of CFD6-4 oilfield in Bohai Sea, the microscopic and macroscopic genetic mechanism of the low resistivity oil layer was systematically analyzed by using clay mineral analysis, scanning electron microscope, particle size analysis, heavy mineral analysis, core nuclear magnetic resonance and other data combined with the study of sedimentary evolution. The research shows that the low resistivity oil layer is rich in clay minerals compared with the conventional resistivity oil layer. The illite mixed layer and illite layer are bridged to fill the pores to form a conductive network. The clay minerals distributed in the porous network fully contact with the formation water to produce cation exchange, forming the microgenesis of the low resistivity oil layer. The complex pore structure leads to high capillary bound water porosity, which also leads to lower oil saturation in low resistivity reservoirs, which constitutes another cause of formation of low resistivity reservoirs. Low-resistance oil reservoirs in the study area are mainly developed at the end of the half-cycle of the rise of the medium-term base level. On the whole, the river energy is weak, and the sand-carrying capacity is reduced. For example, the fine-grained sediment of clay minerals is gradually enriched, and the increase of the proportion of fine-grained sediment causes the complexity of the pore structure of the reservoir, and the increase of the bound water saturation, which constitutes the macro cause of the development of low-resistance oil reservoirs.

The Tanshuling molybdenum deposit is located in the Jiangnan Uplift zone along south part of the Jiangnan Fault. Its main lithology type is granodiorite. With the aim to constrain their magma and ore-forming ages and deposit genesis, combined zircon U-Pb and molybdenite Re-Os geochronology together with whole-rock major and trace element geochemistry have been carried out. The result suggest that the content of SiO₂ is 64.5%~66.8%, Al₂O₃ is 14.4%~16.0%, K₂O is 3.92%~4.86%, Na₂O is 2.90%~3.91%, CaO is 1.56%~2.8%, MgO is 1.24%~1.53%, A/CNK value of 1.02~1.10, and A/NK value of 1.37~1.59. The characteristics of major elements show that the granites belong to metaaluminium to weak peraluminous high potassium calc-alkaline pot-assium series with I-type granite nature. The chondrite-normalized REE patterns are evidently right-declined, with relatively LREE enrichment and slight Eu negative anomalies. The molybdenite Re-Os age of the Tanshuling molybdenite is (133.09±0.86) Ma, and the U-Pb dating of the Maolin granodiorite is (140.4±0.62) Ma, (139.9±0.66) Ma, (139.6±0.63) Ma, all belong to the Early Cretaceous. Integrated chronological and geochemical characteristics show that the main magmatic activity of the Tanshuling molybdenum deposit belong to the Pacific tectonic system, and the alternation of extrusion and extensional has led to large-scale magmatic and mineralization in this area.

To address the challenges of extracting and identifying fault features from roadheader cutting vibration signal, a new fault diagnosis method of roadheader cutting head based on the refine composite multi-scale fuzzy dispersion entropy(RCMFDE) and hippo optimized random forest(HORF) was proposed. Firstly, RCMFDE was used to comprehensively characterize the fault feature information of the roadheader cutting head, and the fault feature data set was constructed. Secondly, the fault type was trained and tested by the HORF to realize the fault pattern recognition of the cutting head of the roadheader. Finally, the proposed method was applied to the experimental data analysis of the cutting head of the roadheader, and compared with the existing multi-scale fuzzy entropy and fine-complex multi-scale spread entropy fault feature extraction methods. The results of the trial indicate that RCMFDE performs better than the other two entropy approaches in discovering defect features, and hippo random forest outperforms extreme learning machine and support vector machine in error recognition. The fault diagnosis method can more correctly recognize the error type of the cutting head of the roadheader, and the rate of accuracy of the recognition obtained 100%.

The emergence of aerial building machines has greatly improved the environment and efficiency of high-rise building operations, while also facing challenges such as increased difficulty in construction operations and complex construction processes. With the continuous deepening of digital transformation in the construction industry, the digital expression of building machine construction processes has emerged as an intuitive and clear solution. It significantly enhances the transparency of the construction process, optimizes resource allocation, and strengthens decision support for project management. An effective pathway for the digital expression of building machine construction processes was established, aimed at advancing high-rise construction towards intelligent management. Through theoretical foundations and field research analysis, the needs for the digital expression of building machine construction processes were identified, leading to the design of a framework for implementing digital expression of building machine construction processes. This research not only provides theoretical guidance for the digital transformation of building machine construction processes but also expands new perspectives on the application of knowledge graphs, interactive electronic technical manuals, model-based definition (MBD) techniques, and augmented reality(AR) technology in the construction field.

With the promotion of green development in civil aviation, aircraft noise has become an issue that cannot be ignored. An improved dynamic window approach (DWA) combining aircraft performance was proposed, which introduces the constraint of continuous climb operations (CCO) and constructs performance constraints for aircraft. To address the problem of rough solution set caused by traversal in traditional DWA algorithm, genetic algorithm(GA) was used for optimization. Secondly, speed was used to represent the time indirectly in order to optimize the track evaluation function. The effect of population distribution was added to make the model more reasonable. Finally, taking the departure direction of BOKIR-8T at Chengdu Shuangliu Airport as an example, the improved algorithm (DWA-GA) was compared with the traditional DWA algorithm, and the flight path under the influence of population distribution was compared, and the aircraft performance parameters and noise influence range were analyzed. The simulation results show that the improved algorithm is more accurate than the traditional DWA algorithm at low resolution, and the population distribution has obvious influence on the track.

For full-bridge LLC resonant converter, intermittent control strategy is an effective means to improve its light load efficiency. An improved intermittent control method was proposed to solve the problems of limited efficiency improvement and large output voltage ripple in light load state of converter by traditional intermittent control. This control method fixes the intermittent conduction time and makes the converter work at the resonant frequency during the intermittent conduction time, which further improves the light load efficiency of the converter and reduces the output voltage ripple. In order to verify the feasibility of the proposed method, a simulation model was built and the simulation waveforms of the traditional intermittent control strategy and the improved intermittent control strategy were compared and analyzed, and an experimental prototype with rated power of 100 W was made. The simulation and experimental results show that the output voltage ripple of the full-bridge LLC resonant converter with the improved intermittent control strategy can meet the engineering requirements, and compared with the traditional intermittent control strategy, the efficiency under light load is improved by up to 4.1%.

Composite material is widely used in aerospace field. It is important to research the damage process of composite and its failure mode. Composite damage is a complex progressive process. In order to predict the strength and damage propagation of reinforced composite wall panels under compression conditions, taking the cap shaped single rib panel under compression load as an example, one instantaneous stiffness degradation model and three continuous stiffness degradation models were used for analysis and comparison. By reducing the stiffness of material points in the element, the damage evolution process of composite materials was simulated, and the experimental results were compared with the analysis results. The comparison results show that all four damage degradation models can accurately predict the bearing capacity and damage range of reinforced wall panels under compression conditions. Compared with other models, the constant type model in the continuous damage degradation model has the highest accuracy. The research results provide theoretical guidance for the study of mechanical properties of composite reinforced wall panels.