Karstic limestone formations in the West Mountain area are important water resources for Taiyuan City in Shanxi Province,northern China,which is also known for its large-scale coal mining *** this study area,groundwat...
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Karstic limestone formations in the West Mountain area are important water resources for Taiyuan City in Shanxi Province,northern China,which is also known for its large-scale coal mining *** this study area,groundwater is not only exploited for water supply purposes but also drained because of coal mining. The process of coal mining changes both the quantity of the karst springs and the quality of karst groundwater system because of overexploitation and *** this paper,the influence of coal mining on the groundwater is analyzed from a qualitative and quantitative perspective. The hydrochemical analysis results reflect the relationship of the recharge,runoff,and drainage;the features of the medium;and water-rock *** on a qualitative understanding of the geological deposition and characteristics of the groundwater flow system,three-dimensional groundwater flow models are established and applied to several scenarios to explore the quantitative influence and allow better protection of the groundwater environment and better utilization of water resources.
In order to improve the positioning accuracy of time of arrival(TOA) in mine and analyse the main factors of positioning error of TOA, a method of TOA positioning for mine to effectively reduce the impact of non-lin...
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In order to improve the positioning accuracy of time of arrival(TOA) in mine and analyse the main factors of positioning error of TOA, a method of TOA positioning for mine to effectively reduce the impact of non-line of sight(NLOS) error propagation is proposed based on the effective suppression of synchronization delay and timing error by symmetrical double-sided two way ranging(SDS-TWR). Firstly, the Kalman filter is used to eliminate the random NLOS delay caused by locomotives and other irregular devices. Then the parameter fitting method and geometric method are used to restrain the errors caused by the fixed NLOS delay in the locating area. The MATLAB simulation results show that the proposed method has a significant inhibitory effect on TOA positioning error and improves the accuracy of TOA positioning in the mine.
To resolve the problems of hazard identification, such as failure to detect existing hazards and the result influenced by the inspectors?subjectivity. A hazard identification system based on a databas
To resolve the problems of hazard identification, such as failure to detect existing hazards and the result influenced by the inspectors?subjectivity. A hazard identification system based on a databas
Laterally constrained inversion(LCI)has been successfully applied to the inversion of dc resistivity,TEM and airborne EM ***,it hasn’t been yet applied to the interpretation of controlled-source audio-frequency magne...
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Laterally constrained inversion(LCI)has been successfully applied to the inversion of dc resistivity,TEM and airborne EM ***,it hasn’t been yet applied to the interpretation of controlled-source audio-frequency magnetotelluric(CSAMT)*** this paper,we apply the LCI method for CSAMT data inversion by preconditioning the Jacobian *** apply a weighting matrix to Jacobian to balance the sensitivity of model parameters,so that the resolution with respect to different model parameters becomes more *** experiments confirm that this can improve the convergence of the *** first invert a synthetic dataset with and without noise to investigate the effect of LCI applications to CSAMT data,for the noise free data,the results show that the LCI method can recover the true model better compared to the traditional single-station inversion;and for the noisy data,the true model is recovered even with a noise level of 8%,indicating that LCI inversions are to some extent noise ***,we re-invert two CSAMT datasets collected respectively in a watershed and a coal mine area in Northern China and compare our results with those from previous inversions,The comparison with the previous inversion in a coal mine shows that LCI method delivers smoother layer interfaces that well correlate to seismic data,while comparison with a global searching algorithm of simulated annealing(SA)in a watershed shows that though both methods deliver very similar good results,however,LCI algorithm presented in this paper runs much *** inversion results for the coal mine CSAMT survey show that a conductive water-bearing zone that was not revealed by the previous inversions has been identified by the *** further demonstrates that the method presented in this paper works for CSAMT data inversion.
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