The potential field determined based on the fictitious compress recovery approach is influenced by the errors contained in the boundary （the Earth＇s surface or the surface corresponding to the satellite altitude） v...The potential field determined based on the fictitious compress recovery approach is influenced by the errors contained in the boundary （the Earth＇s surface or the surface corresponding to the satellite altitude） values. Given the boundary value with definite accuracy, the accuracy of the field determined based on the fictitious compress recovery approach is estimated, and it is theoretically shown that the determined field has the same accuracy level as the given boundary value.展开更多
Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment...Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment model, a formula, which is different from the literatures existing methods, for estimating and identifying the model error, is proposed. On the basis of the proposed formula, an effective approach of selecting the best model of adjustment system is given.展开更多
The solution properties of semiparametric model are analyzed, especially that penalized least squares for semiparametric model will be invalid when the matrix B^TPB is ill-posed or singular. According to the principle...The solution properties of semiparametric model are analyzed, especially that penalized least squares for semiparametric model will be invalid when the matrix B^TPB is ill-posed or singular. According to the principle of ridge estimate for linear parametric model, generalized penalized least squares for semiparametric model are put forward, and some formulae and statistical properties of estimates are derived. Finally according to simulation examples some helpful conclusions are drawn.展开更多
The Gutenberg-Richter law (G-R law) of the magnitude-frequency distribution of earthquakes has been an important base in seismology for a long time. However, the actual magnitude-frequency distribution usually deviate...The Gutenberg-Richter law (G-R law) of the magnitude-frequency distribution of earthquakes has been an important base in seismology for a long time. However, the actual magnitude-frequency distribution usually deviates from the G-R law. Based on the experimental results of three different rock samples, which contain macro-asperity, compressional en-echelon fault and model-Ⅲ shear fault, the correlative coefficient (r) was calculated by fitting the sequences of the acoustic emissions with the G-R law in every scanning time window. We investigated the changes of the correlative coefficient, which describes the actual deviation of magnitude-frequency distribution of earthquakes from the G-R law within the specific scanning time window. According to the results of the rock samples containing macro-asperity and compressional en-echelon fault respectively, the value decreases prior to the rock fracture, meaning that the deviation of magnitude-frequency distribution from the G-R law tends to be larger. The result of the model-Ⅲ shear fault didn’t show obvious decrease before the final rock fracture. Actually, the studies of some earthquakes also show deviation before the occurrence of moderate earthquakes. The results obtained in this paper will provide us with some useful clues for studying precursors before the occurrence of moderate earthquakes with the data of regional earthquake activities.展开更多
基金Funded by the National Natural Science Foundation of China （No.40574004, No.40374004, No.40174004）.
文摘The potential field determined based on the fictitious compress recovery approach is influenced by the errors contained in the boundary （the Earth＇s surface or the surface corresponding to the satellite altitude） values. Given the boundary value with definite accuracy, the accuracy of the field determined based on the fictitious compress recovery approach is estimated, and it is theoretically shown that the determined field has the same accuracy level as the given boundary value.
基金Project supported by the Open Research Fund Programof the Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, WuhanUniversity (No.905276031-04-10) .
文摘Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment model, a formula, which is different from the literatures existing methods, for estimating and identifying the model error, is proposed. On the basis of the proposed formula, an effective approach of selecting the best model of adjustment system is given.
基金Funded by the National Nature Science Foundation of China(No.40274005) .
文摘The solution properties of semiparametric model are analyzed, especially that penalized least squares for semiparametric model will be invalid when the matrix B^TPB is ill-posed or singular. According to the principle of ridge estimate for linear parametric model, generalized penalized least squares for semiparametric model are put forward, and some formulae and statistical properties of estimates are derived. Finally according to simulation examples some helpful conclusions are drawn.
基金This research was sponsored by the Joint EarthquakeScience Foundation,China (A07007)
文摘The Gutenberg-Richter law (G-R law) of the magnitude-frequency distribution of earthquakes has been an important base in seismology for a long time. However, the actual magnitude-frequency distribution usually deviates from the G-R law. Based on the experimental results of three different rock samples, which contain macro-asperity, compressional en-echelon fault and model-Ⅲ shear fault, the correlative coefficient (r) was calculated by fitting the sequences of the acoustic emissions with the G-R law in every scanning time window. We investigated the changes of the correlative coefficient, which describes the actual deviation of magnitude-frequency distribution of earthquakes from the G-R law within the specific scanning time window. According to the results of the rock samples containing macro-asperity and compressional en-echelon fault respectively, the value decreases prior to the rock fracture, meaning that the deviation of magnitude-frequency distribution from the G-R law tends to be larger. The result of the model-Ⅲ shear fault didn’t show obvious decrease before the final rock fracture. Actually, the studies of some earthquakes also show deviation before the occurrence of moderate earthquakes. The results obtained in this paper will provide us with some useful clues for studying precursors before the occurrence of moderate earthquakes with the data of regional earthquake activities.
