| Earthquakes are mainly caused by collisions between plates caused by crustal movement,which compresses underground fluids and causes them to change.Earthquake prediction is the process of accurately predicting earthquakes by monitoring changes in various factors in underground fluids,objectively analyzing data changes during the period.There are many projects for monitoring underground fluids,and the parameters of these projects affect the accuracy of earthquake prediction.The main projects include physical and chemical dynamics of underground fluids,geothermal dynamics,fault soil gas dynamics,and oil and gas well dynamics.In these observation projects,the carbon dioxide concentration in fault soil gas dynamics will have significant changes before earthquakes,And practice has proven that detecting the concentration of carbon dioxide in fault gas is helpful for earthquake research and prediction.Previously,earthquake observation personnel used carbon dioxide rapid detection tubes to detect carbon dioxide concentration,which resulted in significant labor costs.Currently,there are already carbon dioxide analysis instruments for observing earthquake precursors.However,in order to more accurately and professionally monitor the real-time monitoring of carbon dioxide concentration data before earthquakes and provide feedback to the network,this thesis has designed an online analysis instrument specifically for predicting carbon dioxide concentration before earthquakes.The main tasks of this thesis are as follows:(1)Analyze the actual demand for observing the concentration of carbon dioxide gas in earthquake precursors,determine the functional requirements and technical indicators of the instrument,design the specific hardware platform scheme and software functional requirements of the instrument,and complete the selection of all module devices.(2)Based on the determined functional requirements and technical indicators,the hardware platform was built and the structural design of the carbon dioxide data collection section was completed.Complete the porting of the embedded Linux system and the construction of the root file system for the hardware platform with the selected I.MX6 ULL embedded processor as the core,and on this basis,complete the driver design for hardware peripherals;At the application layer,the design and development of the human-machine interaction interface program were completed based on QT development software,and the instrument data communication complies with the "Tenth Five Year Plan" seismic precursor network communication technology regulations.The collected data is sent to the seismic network in real time.(3)The entire instrument was systematically tested.The main functions of the instrument have been debugged and an experimental platform has been established to achieve accuracy testing,repeatability testing,and zero drift testing of the carbon dioxide analyzer.The accuracy of the carbon dioxide concentration data is less than or equal to 1% F.S,the repeatability is less than or equal to 1% F.S for a week,and the zero drift is less than or equal to 0.4% F.S/12 h.The temperature and humidity sensor error test is normal,and all data are within the allowable error range of the instrument,Meet the technical specifications of the instrument,and complete the recalibration of the range loss sensor through a low-cost simple experimental platform. |
PDF Full Text Request