We propose a combined migration velocity analysis and imaging method based on Kirchhoff integral migration and reverse time migration,using the residual curvature analysis and layer stripping strategy to build the vel...We propose a combined migration velocity analysis and imaging method based on Kirchhoff integral migration and reverse time migration,using the residual curvature analysis and layer stripping strategy to build the velocity model.This method improves the image resolution of Kirchhoff integral migration and reduces the computations of the reverse time migration.It combines the advantages of efficiency and accuracy of the two migration methods.Its application in tunnel seismic prediction shows good results.Numerical experiments show that the imaging results of reverse time migration are better than the imaging results of Kirchhoff integral migration in many aspects of tunnel prediction.Field data show that this method has efficient computations and can establish a reasonable velocity model and a high quality imaging section.Combination with geological information can make an accurate prediction of the front of the tunnel geological structure.展开更多
This reflection paper considers the epistemological implications of constructing a digital model of an existing building.The paper compares,in detail,three distinct approaches to constructing a digital model of the Ne...This reflection paper considers the epistemological implications of constructing a digital model of an existing building.The paper compares,in detail,three distinct approaches to constructing a digital model of the New Sacristy at S.Lorenzo in Florence,Italy.Each of the three approaches explores the effects of problematizing the model-building duality.This problematization implicates two conventional assumptions about existing-building models,namely,that they must be geometrically accurate and semantically predictable in order to be useful for research purposes.Proposed counterstrategies of“frictional reciprocity”and“emergent semantics”draw attention to often-overlooked knowledge-production capacities of existing-building models.Thereby,the paper aims to highlight and recommend these strategies as necessary to visioning possible futures,as a viable alternative to conventional modelmaking approaches.展开更多
This paper studies evolutionary mechanism of parameter selection in the construction of weight function for Nearest Neighbour Estimate in nonparametric regression. Construct an algorithm which adaptively evolves fine ...This paper studies evolutionary mechanism of parameter selection in the construction of weight function for Nearest Neighbour Estimate in nonparametric regression. Construct an algorithm which adaptively evolves fine weight and makes good prediction about unknown points. The numerical experiments indicate that this method is effective. It is a meaningful discussion about practicability of nonparametric regression and methodology of adaptive model-building.展开更多
基金sponsored by Nation 973 Program(Grant No.2007CB209603)Nation 863 projection(Grant No. 2006AA06Z108)+2 种基金Nation 863 Program(Grant No.2007AA06Z215)Young Teachers Innovation Fund of Jilin University(No. 421032124424)Graduate Innovation Fund of Jilin University(Grant No.20101059)
文摘We propose a combined migration velocity analysis and imaging method based on Kirchhoff integral migration and reverse time migration,using the residual curvature analysis and layer stripping strategy to build the velocity model.This method improves the image resolution of Kirchhoff integral migration and reduces the computations of the reverse time migration.It combines the advantages of efficiency and accuracy of the two migration methods.Its application in tunnel seismic prediction shows good results.Numerical experiments show that the imaging results of reverse time migration are better than the imaging results of Kirchhoff integral migration in many aspects of tunnel prediction.Field data show that this method has efficient computations and can establish a reasonable velocity model and a high quality imaging section.Combination with geological information can make an accurate prediction of the front of the tunnel geological structure.
文摘This reflection paper considers the epistemological implications of constructing a digital model of an existing building.The paper compares,in detail,three distinct approaches to constructing a digital model of the New Sacristy at S.Lorenzo in Florence,Italy.Each of the three approaches explores the effects of problematizing the model-building duality.This problematization implicates two conventional assumptions about existing-building models,namely,that they must be geometrically accurate and semantically predictable in order to be useful for research purposes.Proposed counterstrategies of“frictional reciprocity”and“emergent semantics”draw attention to often-overlooked knowledge-production capacities of existing-building models.Thereby,the paper aims to highlight and recommend these strategies as necessary to visioning possible futures,as a viable alternative to conventional modelmaking approaches.
文摘This paper studies evolutionary mechanism of parameter selection in the construction of weight function for Nearest Neighbour Estimate in nonparametric regression. Construct an algorithm which adaptively evolves fine weight and makes good prediction about unknown points. The numerical experiments indicate that this method is effective. It is a meaningful discussion about practicability of nonparametric regression and methodology of adaptive model-building.