A new method of 3D transient eddy current field calculation is proposed. The Maxwell equations with time component elimination (METCE) are derived under the assumption of magnetic quasi static approximation, especia...A new method of 3D transient eddy current field calculation is proposed. The Maxwell equations with time component elimination (METCE) are derived under the assumption of magnetic quasi static approximation, especially for the sample of low conductivity. Based on METCE, we deduce a more efficient reconstruction algorithm of a 3D transient eddy current field. The computational burden is greatly reduced through the new algorithm, and the computational efficiency is improved. This new algorithm decompounds the space-time variables into two individual variables. The idea is to solve the spatial vector component firstly, and then multiply it by the corresponded time component. The iterative methods based on METCE are introduced to recover the distribution of conductivity in magneto-acoustic tomography. The reconstructed images of conductivity are consistent with the original distribution, which validate the new method.展开更多
Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the pe...Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation展开更多
Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot an...Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot and ankle fractures展开更多
This article discusses the use of 3D technologies in digital earth applications(DEAs)to study complex sites.These are large areas containing objects with heterogeneous shapes and semantic information.The study propose...This article discusses the use of 3D technologies in digital earth applications(DEAs)to study complex sites.These are large areas containing objects with heterogeneous shapes and semantic information.The study proposes that DEAs should be modular,have multi-tier architectures,and be developed as Free and Open Source Software if possible.In DEAs requiring high reliability in the 3D measurements,point clouds are proposed as basis for the 3D Digital digital earth representation.For the development of DEAs,we propose to follow a workflow with four components:data acquisition and processing,data management,data analysis and data visualization.For every component,technological challenges of using 3D technologies are identified and solutions applied for a case study are presented.The case study is a modular 3D DEA developed for the archaeological project Mapping the Via Appia.The 3D DEA allows archaeologists to virtually analyze a complex study area.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 51137004,61427806 and 51577184the Equipment Development Project of Chinese Academy of Sciences under Grant No YZ201507
文摘A new method of 3D transient eddy current field calculation is proposed. The Maxwell equations with time component elimination (METCE) are derived under the assumption of magnetic quasi static approximation, especially for the sample of low conductivity. Based on METCE, we deduce a more efficient reconstruction algorithm of a 3D transient eddy current field. The computational burden is greatly reduced through the new algorithm, and the computational efficiency is improved. This new algorithm decompounds the space-time variables into two individual variables. The idea is to solve the spatial vector component firstly, and then multiply it by the corresponded time component. The iterative methods based on METCE are introduced to recover the distribution of conductivity in magneto-acoustic tomography. The reconstructed images of conductivity are consistent with the original distribution, which validate the new method.
文摘Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation
文摘Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot and ankle fractures
基金the Mapping the Via Appia project(Funding:NLeSC project code 027.013.901 and NWO project number 380-61-001)。
文摘This article discusses the use of 3D technologies in digital earth applications(DEAs)to study complex sites.These are large areas containing objects with heterogeneous shapes and semantic information.The study proposes that DEAs should be modular,have multi-tier architectures,and be developed as Free and Open Source Software if possible.In DEAs requiring high reliability in the 3D measurements,point clouds are proposed as basis for the 3D Digital digital earth representation.For the development of DEAs,we propose to follow a workflow with four components:data acquisition and processing,data management,data analysis and data visualization.For every component,technological challenges of using 3D technologies are identified and solutions applied for a case study are presented.The case study is a modular 3D DEA developed for the archaeological project Mapping the Via Appia.The 3D DEA allows archaeologists to virtually analyze a complex study area.