Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain c...Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain complexity factor in Raster DEM and TIN DEM is deduced theoretically. In order to make clear how the terrain complexity factor ECF and the average elevation h affect the accuracy of DEM terrain representation RMSEEt, the formula of Gauss synthetical surface is applied to simulate several real terrain surfaces, each of which has different terrain complexity. Through the statistical analysis of linear regression in simula- tion data, the linear equation between accuracy of DEM terrain representation RMSEEt, terrain complexity factor ECF and the average elevation h is achieved. A new method is provided to estimate the accuracy of DEM terrain representation RMSEEt with a certain terrain complexity and it gives convincing theoretical evidence for DEM production and the corresponding error research in the future.展开更多
We prove a generalization of the classical Gauss-Bonnet formula for a conical metric on a compact Riemann surface provided that the Gaussian curvature is Lebesgue integrable with respect to the area form of the metric...We prove a generalization of the classical Gauss-Bonnet formula for a conical metric on a compact Riemann surface provided that the Gaussian curvature is Lebesgue integrable with respect to the area form of the metric.We also construct explicitly some conical metrics whose curvature is not integrable.展开更多
The surface wave signals produced in natural seismic are “intact“ and complex, it is the key which eliminating the noise from that signals if we wanted to invert the structure of the earth using the true signal whic...The surface wave signals produced in natural seismic are “intact“ and complex, it is the key which eliminating the noise from that signals if we wanted to invert the structure of the earth using the true signal which the earth produced.The inter-station fundamental-mode surface wave attenuation coefficient was calculated combined the phase-match filter with frequency-domain Wiener filter. The first, we separated the fundamental-mode surface wave from different two original signal which recorded on two stations which are on one big-circle path using phase-matched filter, and then calculating the attenuation coefficient using frequency domain Wiener filter. It is avoided the negative attenuation coefficient that can't be explained. All of this are the base of inverting the inter structure of the earth.展开更多
基金Supported by Innovation Program of Shanghai Municipal Education Commission (No.10ZZ25)the Key Laboratory of Geo-informatics of State Bureau of Surveying and Mapping (No.200914)
文摘Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain complexity factor in Raster DEM and TIN DEM is deduced theoretically. In order to make clear how the terrain complexity factor ECF and the average elevation h affect the accuracy of DEM terrain representation RMSEEt, the formula of Gauss synthetical surface is applied to simulate several real terrain surfaces, each of which has different terrain complexity. Through the statistical analysis of linear regression in simula- tion data, the linear equation between accuracy of DEM terrain representation RMSEEt, terrain complexity factor ECF and the average elevation h is achieved. A new method is provided to estimate the accuracy of DEM terrain representation RMSEEt with a certain terrain complexity and it gives convincing theoretical evidence for DEM production and the corresponding error research in the future.
基金Support by the Project of Stable Support for Youth Team in Basic Research Field,CAS(Grant No.YSBR-001)NSFC(Grant Nos.12271495,11971450 and 12071449).
文摘We prove a generalization of the classical Gauss-Bonnet formula for a conical metric on a compact Riemann surface provided that the Gaussian curvature is Lebesgue integrable with respect to the area form of the metric.We also construct explicitly some conical metrics whose curvature is not integrable.
文摘The surface wave signals produced in natural seismic are “intact“ and complex, it is the key which eliminating the noise from that signals if we wanted to invert the structure of the earth using the true signal which the earth produced.The inter-station fundamental-mode surface wave attenuation coefficient was calculated combined the phase-match filter with frequency-domain Wiener filter. The first, we separated the fundamental-mode surface wave from different two original signal which recorded on two stations which are on one big-circle path using phase-matched filter, and then calculating the attenuation coefficient using frequency domain Wiener filter. It is avoided the negative attenuation coefficient that can't be explained. All of this are the base of inverting the inter structure of the earth.
