Classical multi-channel technology can significantly reduce the pre-stack seismic inversion uncertainty, especially for complex geology such as high dipping structures. However, due to the consideration of complex str...Classical multi-channel technology can significantly reduce the pre-stack seismic inversion uncertainty, especially for complex geology such as high dipping structures. However, due to the consideration of complex structure or reflection features, the existing multi-channel inversion methods have to adopt the highly time-consuming strategy of arranging seismic data trace-by-trace, limiting its wide application in pre-stack inversion. A fast pre-stack multi-channel inversion constrained by seismic reflection features has been proposed to address this issue. The key to our method is to re-characterize the reflection features to directly constrain the pre-stack inversion through a Hadamard product operator without rearranging the seismic data. The seismic reflection features can reflect the distribution of the stratum reflection interface, and we obtained them from the post-stack profile by searching the shortest local Euclidean distance between adjacent seismic traces. Instead of directly constructing a large-size reflection features constraint operator advocated by the conventional methods, through decomposing the reflection features along the vertical and horizontal direction at a particular sampling point, we have constructed a computationally well-behaved constraint operator represented by the vertical and horizontal partial derivatives. Based on the Alternating Direction Method of Multipliers (ADMM) optimization, we have derived a fast algorithm for solving the objective function, including Hadamard product operators. Compared with the conventional reflection features constrained inversion, the proposed method is more efficient and accurate, proved on the Overthrust model and a field data set.展开更多
Based on Dewey＇s （1933） connotation on reflection, this study focuses on the process ofpre-service EFL （English as a foreign language） teachers＇ reflective thinking. There are eight teachers participating in the...Based on Dewey＇s （1933） connotation on reflection, this study focuses on the process ofpre-service EFL （English as a foreign language） teachers＇ reflective thinking. There are eight teachers participating in the study during their practicum. Their reflective diary, the interviews between the researchers and the teachers, and classroom observation data are triangulated each other. The features of their reflection process are concluded： （1） Their reflections tend to be spontaneous interpretation; （2） their reflective thinking is partly ＂reasoning＂ phases; and （3） they depend on the authorities in the process of reflective thinking. Some implications are made for the guidelines in EFL teachers＇ practicum展开更多
基金We would like to acknowledge the sponsorship of the National Natural Science Foundation of China(42004092,42030103,41974119)Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(Grant No.2021QNLM020001-6)Young Elite Scientists Sponsorship Program by CAST(2021QNRC001).
文摘Classical multi-channel technology can significantly reduce the pre-stack seismic inversion uncertainty, especially for complex geology such as high dipping structures. However, due to the consideration of complex structure or reflection features, the existing multi-channel inversion methods have to adopt the highly time-consuming strategy of arranging seismic data trace-by-trace, limiting its wide application in pre-stack inversion. A fast pre-stack multi-channel inversion constrained by seismic reflection features has been proposed to address this issue. The key to our method is to re-characterize the reflection features to directly constrain the pre-stack inversion through a Hadamard product operator without rearranging the seismic data. The seismic reflection features can reflect the distribution of the stratum reflection interface, and we obtained them from the post-stack profile by searching the shortest local Euclidean distance between adjacent seismic traces. Instead of directly constructing a large-size reflection features constraint operator advocated by the conventional methods, through decomposing the reflection features along the vertical and horizontal direction at a particular sampling point, we have constructed a computationally well-behaved constraint operator represented by the vertical and horizontal partial derivatives. Based on the Alternating Direction Method of Multipliers (ADMM) optimization, we have derived a fast algorithm for solving the objective function, including Hadamard product operators. Compared with the conventional reflection features constrained inversion, the proposed method is more efficient and accurate, proved on the Overthrust model and a field data set.
文摘Based on Dewey＇s （1933） connotation on reflection, this study focuses on the process ofpre-service EFL （English as a foreign language） teachers＇ reflective thinking. There are eight teachers participating in the study during their practicum. Their reflective diary, the interviews between the researchers and the teachers, and classroom observation data are triangulated each other. The features of their reflection process are concluded： （1） Their reflections tend to be spontaneous interpretation; （2） their reflective thinking is partly ＂reasoning＂ phases; and （3） they depend on the authorities in the process of reflective thinking. Some implications are made for the guidelines in EFL teachers＇ practicum
