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Solution and simulation algorithm of microseismic events location to three-dimensional model by comprehensive location method based on Matlab
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作者 XIA Yuan-yuan SHAO He-song +1 位作者 LI Shi-xiong LU Jing-yu 《Journal of Coal Science & Engineering(China)》 2012年第3期254-257,共4页
The essential for microseismic monitoring is fast and accurate calculation of seismic wave source location. The precision of most traditional microseismic monitoring processes of mines, using TDOA location method in t... The essential for microseismic monitoring is fast and accurate calculation of seismic wave source location. The precision of most traditional microseismic monitoring processes of mines, using TDOA location method in two-dimensional space to position the microseismic events, as well as the accuracy of positioning microseismic events, may be reduced by the two-dimensional model and simple method, and ill-conditioned equations produced by TDOA location method will increase the positioning error. This article, based on inversion theory, studies the mathematical model of TDOA location method, polariza- tion analysis location method, and comprehensive difference location method of adding angle factor in the traditional TDOA location method. The feasibility of three methods is verified by numerical simulation and analysis of the positioning error of them. The results show that the comprehensive location method of adding angle difference has strong positioning stability and high positioning accuracy, and it may reduce the impact effectively about ill-conditioned equations to positioning results. Comprehensive location method with the data of actual measure may get better positioning results. 展开更多
关键词 MICROSEISM LOCATION three-dimensional model TDOA POLARIZATION comprehensive location method
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Size-Resolved Water-Soluble Ionic Composition of Ambient Particles in an Urban Area in Southern Poland
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作者 Wioletta Rogula-Kozlowska Izabela Sowka +3 位作者 Barbara Mathews Krzysztof Klejnowski Anna Zwozdziak Kornelia Kwiecinska 《Journal of Environmental Protection》 2013年第4期371-379,共9页
The ambient concentrations of PM-related anions (Cl-, NO3-, SO42-) and cations (Na+, NH4+, K+, Ca2+, Mg2+), total and contained in the PM fractions, were investigated in a typical urban area within the Silesian Agglom... The ambient concentrations of PM-related anions (Cl-, NO3-, SO42-) and cations (Na+, NH4+, K+, Ca2+, Mg2+), total and contained in the PM fractions, were investigated in a typical urban area within the Silesian Agglomeration. A DEKATI low pressure impactor (DLPI) was used to sample PM and separate it into 13 fractions. The PM concentrations were determined gravimetrically, the ion content of the PM water extracts—by means of ion chromatography (Herisau Metrohm AG ion chromatograph). In general, sulfate, nitrate, and ammonia had the greatest ambient concentrations. PM1 contained over 60% of the PM-related sulfate and nitrate mass and 90% of the ammonia mass. Also the majority of Na+ and Cl- were bound onto fine particles. Instead, more of the PM-related K+, Ca2+ and Mg2+ mass were in PM2.5-10 than in PM2.5. In the fine particles (sub-fractions of PM1.6) sulfate, nitrate and ammonia occur mainly as (NH4)2SO4 and NH4NO3. In the sub-fractions of PM1.6-10 sulfate and nitrate might also occur as K2SO4, CaSO4, Ca(NO3)2 or NaNO3. 展开更多
关键词 Ambient Aerosol DEKATI Mass Size Distribution SIA Ammonium Sulfate Ammonium Nitrate Neutralization Ratio Upper Silesia
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