<div style="text-align:justify;"> As a generalized sensor, the RPC model with its accuracy equally matches the physical sensor model. Moreover, the accurate positioning combining with the flexibility i...<div style="text-align:justify;"> As a generalized sensor, the RPC model with its accuracy equally matches the physical sensor model. Moreover, the accurate positioning combining with the flexibility in application leads the RPC model to be the priority in photogrammetry processing. Generally, the RPC model is calculated through a control grid. Different RPC parameters solving methods and the operation efficiency all serve as variables in the accuracy of the model. In this paper, the ridge estimation iterative method, spectrum correction iteration, and conjugate gradient method are employed to solve RPC parameters;the accuracy and efficiency of three solving methods are analyzed and compared. The results show that ridge estimation iterative method and spectrum correction iteration have obvious advantages in accuracy. The ridge estimation iterative method has fewer iteration times and time con-sumption, and spectrum correction iteration has more stable precision. </div>展开更多
Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitri...Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitrinite reflectance(VR),macerals,moisture,volatile matter,ash,total sulfur(S_t)and uranium concentration of CD within the sandstone were studied.The results show that VR ranges from 0.372%Ro to 0.510%Ro with an average value of 0.438%Ro,indicating that CD is in the stage of lignite.The contents of vitrinite(V),inertinite(I)and minerals range from 83.18%–99.48%,0–7.70%,and 0.34%–15.72%,respectively,with the corresponding average value of 95.51%,1.34%,and 3.15%,respectively which indicates that V is the major maceral.Moisture on air dried basis(M_(ad)),volatile matter yield on dry,ash-free basis(V_(daf)),ash yield on dried basis(A_d)and S_t mostly range from 7.95%–16.09%,44.70%–66.54%,4.84%–26.24% and 0.24%–1.12%,respectively,while their average values are 12.43%,53.41%,16.57% and 0.77%,respectively.It suggests that CD is of medium-high moisture,super-high volatile matter,low-medium ash and low sulfur.Uranium concentration ranges from 29 ppm to 92 ppm with an average value of 50 ppm,and uranium concentration increases with the decreased distance to CD.On the whole,M_(ad )and V_(daf) decrease with increasing burial depth,which indicates that CD experienced the burial metamorphism.However,M_(ad) and V_(daf) obviously decrease in uranium-rich areas whereas A_d and S_(t )noticeably increase.Comprehensive studies suggest that there is a certain relationship between uranium enrichment and CD.CD in the stage of lignite helps the adsorption of uranium.On one hand,radioactivity uranium enrichment makes organic matter maturation increase with a decrease in moisture and volatile matter.On the other hand,an increase in organic matter maturation,caused by radioactivity uranium enrichment,results in an increase in uranium minerals,which is instructive in the study of regional uranium mineralization and metallogenic regularity.展开更多
文摘<div style="text-align:justify;"> As a generalized sensor, the RPC model with its accuracy equally matches the physical sensor model. Moreover, the accurate positioning combining with the flexibility in application leads the RPC model to be the priority in photogrammetry processing. Generally, the RPC model is calculated through a control grid. Different RPC parameters solving methods and the operation efficiency all serve as variables in the accuracy of the model. In this paper, the ridge estimation iterative method, spectrum correction iteration, and conjugate gradient method are employed to solve RPC parameters;the accuracy and efficiency of three solving methods are analyzed and compared. The results show that ridge estimation iterative method and spectrum correction iteration have obvious advantages in accuracy. The ridge estimation iterative method has fewer iteration times and time con-sumption, and spectrum correction iteration has more stable precision. </div>
基金supported by the 973 Project (No. 2015CB453003)Open Fund of Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences), Ministry of Education (No. TPR-2015-09)+2 种基金Geological Survey Foundation of Ministry of Finance of the People’s Republic of China (No. 12120115013701)Natural Science Foundation of China (No. 41502105)Fundamental Research Funds for the Central Universities, China University of Geosciences(Wuhan) (No. G1323511660)
文摘Carbonaceous debris(CD)is widely distributed in the sandstone of the Daying Uranium Deposit,northern Ordos Basin,and coexists with uranium minerals,which provides a favorable case for studying their relationship.Vitrinite reflectance(VR),macerals,moisture,volatile matter,ash,total sulfur(S_t)and uranium concentration of CD within the sandstone were studied.The results show that VR ranges from 0.372%Ro to 0.510%Ro with an average value of 0.438%Ro,indicating that CD is in the stage of lignite.The contents of vitrinite(V),inertinite(I)and minerals range from 83.18%–99.48%,0–7.70%,and 0.34%–15.72%,respectively,with the corresponding average value of 95.51%,1.34%,and 3.15%,respectively which indicates that V is the major maceral.Moisture on air dried basis(M_(ad)),volatile matter yield on dry,ash-free basis(V_(daf)),ash yield on dried basis(A_d)and S_t mostly range from 7.95%–16.09%,44.70%–66.54%,4.84%–26.24% and 0.24%–1.12%,respectively,while their average values are 12.43%,53.41%,16.57% and 0.77%,respectively.It suggests that CD is of medium-high moisture,super-high volatile matter,low-medium ash and low sulfur.Uranium concentration ranges from 29 ppm to 92 ppm with an average value of 50 ppm,and uranium concentration increases with the decreased distance to CD.On the whole,M_(ad )and V_(daf) decrease with increasing burial depth,which indicates that CD experienced the burial metamorphism.However,M_(ad) and V_(daf) obviously decrease in uranium-rich areas whereas A_d and S_(t )noticeably increase.Comprehensive studies suggest that there is a certain relationship between uranium enrichment and CD.CD in the stage of lignite helps the adsorption of uranium.On one hand,radioactivity uranium enrichment makes organic matter maturation increase with a decrease in moisture and volatile matter.On the other hand,an increase in organic matter maturation,caused by radioactivity uranium enrichment,results in an increase in uranium minerals,which is instructive in the study of regional uranium mineralization and metallogenic regularity.
