Abstract:As Haoji Railway is only 130 m away from Lushi Geomagnetic Station,the geomagnetic observation data of Lushi Station has been seriously disturbed during construction and operation,resulting in unavailable data.The purpose of this paper is to conduct in-depth analysis on the typical events that caused the change of the second sampled geomagnetic data of Lushi Station during the operation of Haoji Railway.Based on the analysis of the characteristics of the time domain and frequency domain of the geomagnetic data of Lushi Station,the FFT observation anomaly recognition method based on the triple mean square error principle is proposed to distinguish the observation anomaly caused by the railway operation from the normal magnetic disturbance for identification.The actual reconstruction effect of spatial weighting method,BP neural network algorithm and XGBoost strong machine learning algorithm in data processing is verified by data reconstruction for the disturbed observation data and missing data of Lushi Station.The results show that when the XGBoost strong machine learning algorithm is applied to the data reconstruction of observation anomalies and missing records.,through data simulation,the reconstructed data has a high degree of coincidence with the original data in a small time scale,achieving good results.

Abstract:Artificial Intelligence(AI)technology has gradually formed a new technical paradigm in the field of offshore seismic data processing.This paper focuses on the systematic application of AI pattern recognition methods in marine geophysical exploration,and builds a multi-task processing system based on deep learning for the strong noise interference,tectonic interpretation uncertainty and bottleneck of thin reservoir identification existing in offshore seismic data.Intelligent noise suppression is achieved by designing a convolutional denoising self-encoder,precise identification of geological formations is accomplished by adopting Mask R-CNN architecture,and the reservoir parameter prediction model is optimized by combining with the long and short-term memory network.

Abstract:The failure of elevator systems during earthquakes represents a critical vulnerability in the emergency response of high-rise buildings.The conventional operational mode,where mechanical and electrical subsystems function independently,is inadequate for addressing coupled failure risks under complex seismic loads.This study analyzes the seismic failure pathways of both elevator mechanical structures and electrical systems,elucidating the causes of typical malfunctions such as landing failures due to alarm delays and aggravated passenger entrapment caused by communication interruptions.To enhance the functional continuity of elevator systems under strong earthquakes,a framework integrating the following strategies is proposed:a mechanical-electrical state coupling response mechanism for real-time fault information exchange,an asymmetric magnitude response strategy to dynamically allocate functional weights between subsystems according to varying seismic intensities,and a cross-system safety closed-loop management model.The findings offer theoretical and practical insights for the seismic design of elevators in high-rise buildings.

Abstract:Based on historical earthquake examples,by analyzing the fixed-point deformation observation data of Yunlong Station from 2013 to 2023,the threshold of precursor anomalies and the characteristic images of imminent anomalies were obtained,providing a reference example for identifying precursor anomaly information of Yunlong Station's fixed-point deformation.The research results indicate that the short-term anomalies of water pipe tilt observation are mainly manifested as solid tide distortion and accelerated inclination,with a seismic interval≤60 days.It has good short-term indication for medium-strong earthquakes with M≥5 within a range of≤200 km around the measuring point.The strain observation of the cave body adopts the rate difference method with a threshold of 1.5 times the standard deviation,and the window anomaly method and the annual variation detection method take a threshold of 1 time the standard deviation.Earthquakes occur during the abnormal process or within 90 days after the end of the anomaly,with a prediction accuracy of 75%,all of which are evaluated by the R-value prediction efficiency.The three prediction indicators have important reference significance for the prediction of moderate-earthquakes within 300 km around the measuring point and can be applied to earthquake prediction practice as quantitative prediction indicators for tracking.Especially,the window anomaly method shows the advantages of high prediction accuracy,low false alarm rate and low omission rate.This indicator can be mainly used for strong earthquake prediction in western Yunnan.

Abstract:To accurately extract and arrange keywords from the Chinese text of scientific research papers,a keyword extraction method for Chinese text of scientific research papers based on semantic features and the TextRank algorithm was studied.A semantic feature-based method for selecting candidate keywords from Chinese text of scientific research papers was used.In the Word2Vec tool,the Chinese text was converted into a word vector as the semantic features of the Chinese text of the paper.The semantic features were input into convolutional neural networks,and the semantic features belonging to candidate keyword types were extracted through classification.The text words they belong to were used as candidate keywords.By using the TextRank algorithm-based keyword extraction method for Chinese text of scientific research papers,a graph model for extracting keywords was constructed by using the average information entropy,part of speech,and position of the candidate keywords as the keyword extraction indicators.The comprehensive weights of the candidate keywords were calculated,and the candidate keywords were arranged in descending order.The top-ranked candidate keywords were used as the final extracted keywords to complete keyword extraction from Chinese text of scientific research papers.The tests show that this method can improve the accuracy of keyword extraction and keyword ranking in Chinese text of scientific research papers.

Abstract:Based on the data from 10 stations of the Suqian Seismic Array for fault soil gas observation in the past three years,this paper analyzed the characteristics of radon,hydrogen,and carbon dioxide emission concentra-tions and studied the relationship between the emission concentration of different types of soil gases and faults in dif-ferent geological periods.Moreover,the extent to which the annual variation of the data was influenced by tempera-ture,air pressure,and rainfall was explored.Combined with the ML3.7 earthquake in Sihong,the radon data in soil gases showed the phenomenon of synchronous trend change,and the seismic reflection ability of the seismic ar-ray was analyzed.The results show that the dynamic changes of radon,hydrogen,and carbon dioxide concentra-tions in soil gas are closely related to climatic factors.Radon observations are affected by rainfall and the carrier gas role of carbon dioxide.The synchronous trend changes in the array data have indicative significance for the detec-tion of pre-earthquake anomalies.

Abstract:This paper collected data of 344 historical earthquake disasters in Yunnan Province from 1900 to 2023.Based on ArcGis,mathematical statistics were used to analyze the characteristics of temporal and spatial distribution,casualties,and economic losses of earthquake disasters in Yunnan Province.The Yunnan historical earthquake disaster information service system is established by using RESTful architecture,.NET Core,Echarts,and Three.js technologies.The functions of statistics,inquiry,and visual display of historical earthquake disaster information in Yunnan Province is realized,which provides reference for assessing earthquake disaster risks and earthquake disaster emergency decision-making.

Abstract:Based on the coseismic response recorded by the water level of Shilin well in Yunnan Province in the past six years,this paper analyzed the characteristics and mechanism of the coseismic response of Shilin observation well in combination with actual cases.It was preliminarily discussed that the water level showed rapid high-frequency oscillation and multiple oscillations during distant major earthquakes,gradually attenuated,and then returned to normal.In short-distance major earthquakes,the water level showed steps up and down.The duration and amplitude of both were related to the magnitude and well-to-epicenter distance.The results show that the coseismic response amplitude of water level of Shilin well is correlated with well-to-epicenter distance and magnitude,but it is not completely linear.The coseismic response time is later than the time when the earthquake occurs,and there is a lag.The relationship between magnitude,well-to-epicenter distance,and lag time is positively correlated.The larger the magnitude,the farther the distance,the longer the lag time;the smaller the magnitude,the closer the distance,the shorter the response time.

Abstract:Upgrading the overall level of earthquake resistance of rural buildings is the key to disaster prevention and mitigation.Lushan County,Ya'an City,Sichuan Province,is located in an earthquake-prone area with high seismic risk.In order to grasp the current status of the seismic capacity of rural buildings in Lushan County,this paper carried out a sample survey of rural buildings in 8 townships and 14 villages in Lushan County,so as to count the proportions and characteristics of buildings of different structural types and identify the weaknesses of rural buildings in seismic design and construction.On this basis,the paper used the RISK-UE susceptibility index method to estimate the possible seismic damage of rural buildings under different seismic intensities and proposed targeted recommendations for improving the seismic resilience of buildings.The results show that the study area as a whole exhibits slight to moderate seismic damage under seismic intensity VII.Among them,Hexi Village,Kuaile Village,and Hebian Village,which have a smaller proportion of fortified brick-concrete houses,may experience more severe seismic damage compared to other villages.The results of the study provide a scientific basis for the seismic reinforcement and disaster prevention and mitigation of rural buildings in Lushan County.

Abstract:This paper proposed an estimation model of joint distributions of structural system extreme responses under random excitation based on multivariate Gumbel Copula function and generalized extreme distributions,gave the estimation method of model parameters based on response samples,and established the joint probability calculation method of network disjoint shortest paths and cuts based on joint distributions of extreme responses,which is used for effective analysis of the connectivity reliability of the failure dependent engineering systems.The multivariate extreme value estimation of the random seismic response of a six-story shear-building model and the seismic dynamic reliability analysis of the equipment system of substation validate the effectiveness of the estimation model of the joint distributions of the extreme responses of the structure proposed in this paper and the joint probability calculation method of the network disjoint shortest paths and cuts based on the joint distributions of the extreme responses.

Abstract:On October 24,2023,the MS5.5 earthquake in Subei,Gansu Province occurred on the NWW-trending fault zone at the northern edge of the Qilian Mountains,with a thrust type focal mechanism.Before the earthquake,there were 5 seismic anomalies in the central and western sections of the Qilian Mountains.Among them,there was a new MS3 earthquake anomaly in the western section of the Qilian earthquake zone one month before the earthquake.In July 2023,the strain EW component of the Xigou Cave in Jiayuguan changed from tension to compression,and the NS component showed a decrease in annual amplitude.114 days later,54 km away from the measuring point,a MS5.5 earthquake occurred in Subei,Gansu Province.In the two days before the main earthquake,there was a significant increase in seismic activity in the southeast direction,with a total of 26 recorded earthquake events,the largest of which was Subei MS4.7 earthquake on October 22,2023.It entered a calm period about 7 hours before the main shock and then the main shock occurred.This paper summarizes the abnormal changes in various measurement items before Subei MS5.5 earthquake,as well as the experience accumulated in determining the occurrence of the main earthquake by determining the foreshock sequence,and adds new earthquake examples to earthquake prediction research.

Abstract:This article investigated rural residential buildings in 14 natural villages and 10 towns in Yindu District,Anyang City,through face to face interaction and village and household visits.The seismic performance of buildings was analyzed in terms of structural types,construction years,and structural characteristics.The results show that the proportion of masonry structures in rural residential buildings in Yindu District is high,and the construction years mainly range from 1980s to 2000s;the proportion of unreinforced masonry structures is the highest.The joint of longitudinal and transverse walls of the new(existing)buildings is not protected with structural measures to ensure its reliable connection.The window lintels are made of bricks,and there were even no lintels.The concrete lintels lack support lengths that meet the standards on the walls.Large doors and windows of the new(existing)buildings generally are installed on the south longitudinal walls,resulting in significant differences in stiffness between the front and rear longitudinal walls.Stairs are generally arranged at the ends or corners of buildings,causing stress concentration and the torsion is increased.Based on this,it is proposed that there are some problems in rural residential buildings in Yindu District,such as irregular plane(facade),non-standard design and construction,and weak awareness of earthquake prevention and disaster reduction among residents.Finally,some reasonable suggestions are put forward to provide a scientific basis for the research on the seismic performance of residential buildings in Henan Province.

Abstract:Based on the actual work requirements,this paper developed a time-domain monitoring and frequency-domain power spectrum density(PSD)calculation software for the VP broadband inclinometers on the Matlab platform.The software utilized the Matlab network functions to monitor the VP broadband inclinometer in real time to obtain data and display it visually.At the same time,it used the principle of the improved periodogram diagram method(Welch method)to automatically calculate the PSD of the daily observation data.It executed the time-domain monitoring and frequency-domain PSD calculation tasks concurrently in multiple threads through the Matlab parallel computing toolbox,without interfering with each other.After testing,the software could achieve real-time monitoring of multiple VP broadband inclinometers and promptly issue alarms for situations such as data breakage and out-of-range.This helped improve the quality of observational data at the station.Additionally,by automatically calculating the PSD of the observational data,it enabled station staff to analyze and summarize the normal background and interference characteristics of the observation data,thereby facilitating dynamic tracking and understanding of the background noise situation at the station.

Abstract:This paper analyzed the data of 831 hazardous chemical warehouses in Tianjin City based on enterprise portrait technology.It conducted an early assessment of earthquake disasters by fitting the actual seismic intensity and evaluated the risk level of the hazardous chemical warehouses by extracting their risk eigenvalues.Then,the paper provided decision-making suggestions based on the risk level.At the same time,it built a visual management platform for hazardous chemical warehouses by using the B/S architecture.By calling the Baidu Map's API,the lo-cal database of hazardous chemical warehouses was retrieved and accessed,enabling the map-based visualization application of hazardous chemical warehouse information and the generation of emergency decision-making sugges-tions after the earthquake,which can effectively reduce the risk of secondary disasters caused by earthquakes and improve the earthquake resistance and disaster prevention capabilities and levels of the city.

Abstract:Taking the sites of three seismic stations in Jinping,Malipo,and Hekou,Yunnan Province as exam-ples,this paper explained the quality of the station foundation revealed by the degree of dispersion of the power spectrum curves by comparing the differences in the 24-hour background noise power spectrum curves of the sites of the preliminary survey and re-survey stations.The station sites with a high degree of dispersion of the power spec-trum curves were susceptible to the influence of interference,whereas those with a convergent and low degree of dispersion of the power spectrum curves had a superior quality and were not susceptible to the influence of near-field interference.This result suggests that the degree of dispersion of power spectrum curves is indicative of the im-munity of the station sites to near-field interference.Further investigation indicates that the low-frequency disper-sion of the power spectrum curve of short-period seismometer recording data mainly originates from the equivalent tilt signals recorded outside the passband.Conversely,the interfering signals in the high-frequency band predomi-nantly emanate from the near-field vibrational interferences.The key to reducing the aforementioned interference lies in setting up the instrument on bedrock rather than on rolling stones.This hypothesis has been substantiated by the subsequent re-survey.

Abstract:Urban underground pipeline networks are the lifeline of a city and play a critical role in ensuring its normal operation.However,traditional underground pipeline data is often presented only in tabular formats,which fail to provide an intuitive representation of the pipelines' location.This can lead to accidents during construction,such as inadvertently breaking pipelines.This paper utilizes Revit API for secondary development to automatically read underground pipeline network data from Excel spreadsheets,convert the underground pipeline network data into a building information modeling(BIM)model,and integrate the BIM model with the GIS system based on the geodetic coordinate positions.It enables the viewing of the actual positions of the underground pipeline network in the GIS system.This not only significantly improves the efficiency of BIM modeling for the underground pipeline network but also provides a basic platform for the digital operation and maintenance of underground pipeline network of the whole city.

Abstract:Based on the data of 134 earthquakes with M≥6.0 in Chinese mainland since 1976,the paper presents a statistical analysis of the rupture types,sequence types,magnitude difference between the main shock and the largest aftershock,time interval,as well as the relationship between sequence types and small and medium-sized seismicity in the pre-mainshock epicentral region.It is found that 90%of the largest aftershocks occurred within 90 days after the main shock.According to the classification of rupture types,the proportion of main and after types in each type is more than 60%,and the proportion is higher in strike-slip type and normal fault type,while the proportion of isolated type is lower in strike-slip type,there is no isolated earthquake in the normal fault type.Isolated earthquakes usually occur in regions where earthquakes are relatively inactive,and with the increase of the magnitude of the main earthquake,the proportion of isolated sequences decreases significantly.Based on the relationship between the largest aftershock within 24 hours after the main shock and the largest aftershock,it is found that the larger the largest aftershock within 24 hours,the smaller the subsequent largest aftershock.If the magnitude difference between the largest aftershock within 24 hours and the main shock is less than one magnitude or more than 2.5 magnitude,the probability of a subsequent larger aftershock is 18.2%for the former and 89.5%for the latter.These statistical rules can be used to estimate the largest aftershocks in different time periods before and after an earthquake.

Abstract:This study focused on the public opinion guidance mechanism of post-earthquake news coverage on the reconstruction process of disaster areas and constructed an analytical framework based on agenda-setting theory and emotional motivation theory.A stratified sampling of 360 public questionnaires and media texts was collected and a hierarchical regression analysis was used to empirically examine the role of frequency of reporting,type of framing,and public participation behavior.It is found that the frequency of reporting significantly enhances the public concern for reconstruction,but there is a law of diminishing marginal effect;the heroic reporting framework effectively promotes the willingness to donate through the mediation of empathic emotion,forming a fully mediated path;the positive effect of scientific reconstruction framework on the degree of policy support is moderated by the level of public education.

Abstract:Taking Chenda Town in Sanming City as the research object,this paper discussed the application value of shallow geophysical exploration in urban earthquake prevention and disaster reduction.By adopting a detection method mainly based shallow seismic shear wave reflection exploration and supplemented by geological radar detection,the structural conditions of underground rock formations and fault distributions in this area were demonstrated.It is pointed out that shallow geophysical exploration can effectively improve the seismic capacity of cities and provide scientific basis for geological safety assessment,and it is also necessary to strengthen interdisciplinary integration and data processing accuracy to optimize urban earthquake prevention and disaster mitigation strategies.

Abstract:Due to the inability of traditional research on the seismic performance of bridge bearings to simulate different seismic scenarios and parameter changes,and the inability to conduct multidimensional evaluations of the performance of large-span bridges,the seismic performance of large-span bridge bearings is poor.To solve this problem,a large-span railway steel truss arch bridge was selected as the research object.Four different types of supports were selected,and a three-dimensional spatial finite element model of the research object was constructed by using the three-dimensional spatial finite element software Abaqus.The seismic performance of the research object's bearings under different ground motion input conditions was analyzed.The results show that the friction pendulum reduction and isolation bearings have a significant limiting function within the research object,which suppresses the longitudinal bridge deformation level of all bearings within the range of 0.85 m.The research object uses friction pendulum reduction and isolation bearings to exert corresponding constraint effects on the displacement of the main beam under seismic action.Under the influence of ground motion,friction reduction and deformation of isolation bearings are greater than their free path state,and their limiting function is activated to generate longitudinal constraints,resulting in an increase in the seismic internal force value transmitted from the upper structure of the research object to the bridge tower pier.After using friction pendulum reduction and isolation bearings,the research object can achieve collaborative seismic resistance between different bridge piers under different ground motion conditions.The research object maintains an elastic state under different seismic ground motions after using friction pendulum reduction and isolation bearings,which meets the expected seismic target.