Based on theoretical analysis, this paper selects panel data from 31 provinces(due to the lack of data, the statistical data mentioned here do not include the Hong Kong Special Administrative Region, the Macao Special Administrative Region and Taiwan Province)in China to study the impact of population aging on the effectiveness of monetary policy. The results show that the aging of the population significantly weakens the effectiveness of monetary policy. From the perspective of regional heterogeneity, the more severe the population aging, the stronger the inhibitory effect of population aging on monetary policy. Further research finds that population aging affects the effectiveness of monetary policy by weakening the credit channels of monetary policy. Finally, it is proposed that the age factor of the population should be fully considered, and the relevant policy suggestions should be carefully evaluated such as the intermediary target and the prediction effect of monetary policy.

In order to make the virtual power plant(VPP) better integrate resources, and then realize product packaging and market transactions, using the natural geographic space attributes of energy resources to combine the demand-side energy of the virtual power plant with GIS(geographic information system) combined, a GIS-based evaluation model for demand-side energy is proposed. The composition of demand-side energy was analyzed, and the index system of the evaluation model was established. The index system of the evaluation model was refined, the common index and difference index were proposed, and the quantification method was given.AHP, entropy weight method and weighted sum are used to realize the calculation method of the standardization of evaluation indicators, the weight of common indicators, the weight of difference indicators and the evaluation model. The evaluation model method was analyzed through the data of 10 regions to provide quantitative methods and scientific support for the construction of virtual power plants for resource optimization aggregation.

Quantitative models are one of the core challenges for investors in stock dynamic prediction. The original LSTM(long short-term memory) stock prediction model was affected by noise in the input data, which interfered with the prediction effect. In this paper, there are 259 indicators that affect stock prices. Firstly, the input data was reduced in dimensionality using dimensionality reduction methods to preserve key information, and then input into LSTM to form an improved prediction model, namely PCA-LSTM model, ISOMAP-LSTM model, and PCA-ISOMAP-LSTM model. Through empirical comparison, compared with the original LSTM prediction model and the attention mechanism model MHA-LSTM, the PCA-LSTM model and ISOMAP-LSTM model reduce training time. The average absolute error (MAE), average relative error (MAPE), and root mean square error (RMSE) in the prediction error evaluation indicators are significantly reduced, and the average rise and fall accuracy (ARRF) is significantly improved. However, the PCA-ISOMAP-LSTM model has an increase in error rate and a certain decrease in accuracy. The Diebold Mariano test also showed that the PCA-LSTM model and ISOMAP-LSTM model have stronger stock prediction abilities than the original LSTM model and MHA-LSTM model, while the PCA-ISOMAP-LSTM model and MHA-LSTM model have weaker prediction abilities than the original LSTM model. The difference in prediction accuracy between the PCA-LSTM and ISOMAP-LSTM models is not significant, and both can be used as a new technical support for quantitative stock investment.

Multi-source heterogeneous geological big data is difficult to ensure accuracy during the structuring process. By constructing a standard stratigraphic system for Nanning basin and using the automatic borehole modeling method of the Nanning Geological Spatial Big Data Analysis System to create a 3D geological model, four factors were considered—engineering geological zoning, age strata, geological genesis types, and lithology—to assist in the rapid cleaning and processing of structured database entries. The results show that discontinuous areas, abrupt change areas, and topological error areas in the 3D geological model can quickly identify issues such as duplicate, abnormal, and missing structured data, effectively improving the speed and accuracy of error identification.

A comprehensive analysis of air distribution and thermal comfort assessment within large-scale heating, ventilation, and air conditioning(HVAC) systems holds significant value in enhancing indoor thermal comfort levels and reducing energy consumption. In order to improve the use comfort of irregular large space air conditioning and reduce the impact of the installation position of air conditioning indoor unit on the comfort of air conditioning, the construction party carried out software simulation test on the service hall on the second floor of a tourist center in Guangyuan City with the help of computational fluid dynamics (CFD) simulation software Fluent, and deepened the design of the area. In the simulation, it is found that although the comfort level of the service hall meets the standard requirements, there is still a large space for optimization. Therefore, the drawings were further designed according to the simulation results of the CFD software. After the deepening design, the simulation results were improved from local regional level and large area level to local regional level and large area level I. Finally, the actual wind speed and temperature of the service hall are compared with the simulation results. The results show that, except for a small part of the temperature and wind speed affected by the doors and Windows and personnel flow, other areas have less error with the simulation results. With the help of specific examples, the positive feedback idea of the construction party on the comfort control of the air conditioning system is opened, the scientific nature of the construction party in the project construction is improved, which provides some ideas and experience for the construction party to put forward the deepening design.

The Neogene loose sandstone has the characteristics of low diagenesis and poor cementation. Its structure is loose, and groundwater is easily enriched in this formation, making it the main seepage channel for groundwater. Based on the Xiangshan No.2 Tunnel, the application technology of the advanced support system of horizontal rotary jet grouting piles in the formation of mudstone interbedded with loose sandstone was systematically studied through on-site pile testing and numerical simulation. The secondary supplementary grouting technology was proposed to improve several technical deficiencies of the horizontal rotary jet grouting piles and solve the frequent problems of collapse of the face and sudden water and mud influx during the excavation process of Xiangshan No.2 Tunnel. A simplified calculation method for horizontal rotary jet grouting piles based on rod structure is proposed by refining the calculation model, which will facilitate the promotion and application of this support system.

The safety cover thickness required for TBM (tunnel boring machine)tunneling in hard rock is such that it is too large to increase the total length of the tunnel design without increasing the cost. Therefore, the study of the minimum safety cover thickness for TBM tunneling in hard rock is of great engineering significance. In light of the aforementioned considerations,the Guangzhou-Dongguan-Shenzhen Intercity Railway Xixiang Station-Bao’an Station double-mode shield tunnel project case was drawn upon to investigate the minimum safe overburden thickness of varying parameters under the condition of changing rock grades. The results indicate that when the arch displacement method is employed, if the tunnel perimeter rock class is II or III, and the thickness of soft soil is between 0 and 3 times the diameter of the tunnel, then the minimum safe rock cover thickness is between 0.2 and 1.2 times the diameter of the tunnel. When the pressure arch method is employed for simulation, if the rock cover class is II or III, and the soft soil thickness is between 1 and 3 times the tunnel diameter, the ratio of the minimum rock cover thickness to the depth of burial exhibits a tendency to increase and then decrease with the increase of the hard rock thickness,reaching a maximum value of 0.39. When the overburden grade is grade IV and the thickness of the soft soil is 1 to 3 times the diameter of the tunnel, the ratio of the minimum rock cover thickness to the depth of burial is observed to decrease with the increase of the hard rock thickness, reaching a maximum value of 0.42. The conclusions can provide engineering guidance for TBMs to safely tunnel through hard rock.

In the process of large-diameter slurry shield tunneling, encountering boulder groups in front of the cutter head often occurs, which significantly impact tunneling efficiency and construction safety. To achieve rapid and efficient handling of boulder groups closely adjacent to the slurry shield cutter head, reduce the frequency of pressure-compromised opening for tool replacement, and ensure safe and smooth passage through boulder areas, the Fuzhou Metro Binhai Line project’s Binhai Zhong section was taken as a case study. Through in-depth analysis of key aspects such as tunneling anomalies, tool inspections, tool replacements, ground re-examinations, and handling of boulders adjacent to the cutter head, innovative techniques and processes such as the “rock crushing and downward pressure method” and the “rock pushing and filling method” have been proposed. These effectively address the challenges posed by boulder groups encountered during large-diameter slurry shield tunneling, significantly shortening the construction period for passing through boulder areas and providing a systematic solution and reference for similar projects.

In order to study the stability of the geological conditions of the water transmission and power generation system of Qichun pumped storage power station, and selecting the optimal scheme, engineering geological surveying, high-density electrical method, and geostress test were carried out in the engineering area to qualitatively and quantitatively describe the geological conditions of the engineering area. The advantages and disadvantages of multiple schemes of water transmission and power generation systems were analyzed based on the rock and soil stress state. The results showed that the three faults reduced the engineering geological stability of the western route plan, so the eastern route plan was selected. In addition, the stress conditions of both the central and tail underground power plants meet the requirements of engineering geology and hydrogeology. However, the stress distribution of the central power plant is more uniform and there are no fractures that restrict geological stability. Therefore, a better central power plant scheme is selected.

At the present stage in China, the situation of rural domestic sewage collection and treatment is grim, and management is difficult. Rural domestic wastewater treatment has become one of the important tasks in the implementation of rural revitalization strategy. Focusing on rural MBR membrane treatment stations, the influence of water quality on their operating conditions was comprehensively analyzed. Key water quality parameters including chemical oxygen demand(COD), ammonia nitrogen (NH₃-N), total phosphorus(TP), and suspended solids (SS) were analyzed in detail to clarify the characteristics of wastewater quality. In terms of sludge characteristics, the capillary suction time (CST) was used to evaluate the sludge dewatering performance, and it is found that the change of water quality could change the difficulty of sludge dewatering. Using bioinformatic analysis, it is revealed that the structure of microbial community was intrinsically linked to water quality parameters, and the relative abundance of species under different water quality conditions showed obvious differences and was closely related to the treatment efficiency. With the help of membrane fouling monitoring methods, such as transmembrane differential pressure(TMP) measurement, the membrane fouling status can be grasped in real time. Through correlation analysis, it is found that there are complex associations between water quality parameters, sludge characteristics and biological information, which affect the operation of rural MBR membrane treatment stations, providing a comprehensive theoretical basis and data support for the precise control of the operation of the stations, which can help to improve the efficiency and quality of rural wastewater treatment and reduce the operating costs.