caa a22 4500 47707507X CHVBK 20180405111437.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF02827583 doi (NATIONALLICENCE)springer-10.1007/BF02827583 An improved iterative reconstruction algorithm for traveltime tomography [Elektronische Daten] [Ma Ning, Hu Zhengyi, Tang Xueyuan, Wang Yanping] Traveltime tomography is a technique to reconstruct acoustic, seismic, or electromagnetic wave-speed distributions from first arrival traveltime data. The ray paths that should be used for tomographic techniques strongly depend on the wave-speed distribution. In this paper, a new method is proposed for finding out the ray paths from Fermat's principle, that means the traveltime of the ray path should be a minimum value. The problem of finding out the ray path is actually an optimum problem. Our new method uses the idea to find out the shortest path in a weighted directed graph to solve the problem. The ray paths found out by this method are used in the iterative reconstruction algorithm. Computer simulation result produced by this reconstruction algorithm is better than that by the conventional ones. It also shows that the new algorithm is effective with good convergency and stability. Springer, 1996 traveltime tomography nationallicence Fermat's principle nationallicence weighted directed graph nationallicence Ning Ma College of Electronic Information, Wuhan University, 430072, Wuhan, China aut Zhengyi Hu College of Electronic Information, Wuhan University, 430072, Wuhan, China aut Xueyuan Tang College of Electronic Information, Wuhan University, 430072, Wuhan, China aut Yanping Wang College of Electronic Information, Wuhan University, 430072, Wuhan, China aut Wuhan University Journal of Natural Sciences Wuhan University 1/1(1996-03-01), 67-70 1007-1202 1:1<67 1996 1 11859 https://doi.org/10.1007/BF02827583 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02827583 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ning Ma College of Electronic Information, Wuhan University, 430072, Wuhan, China aut NATIONALLICENCE 700 1- Zhengyi Hu College of Electronic Information, Wuhan University, 430072, Wuhan, China aut NATIONALLICENCE 700 1- Xueyuan Tang College of Electronic Information, Wuhan University, 430072, Wuhan, China aut NATIONALLICENCE 700 1- Yanping Wang College of Electronic Information, Wuhan University, 430072, Wuhan, China aut NATIONALLICENCE 773 0- Wuhan University Journal of Natural Sciences Wuhan University 1/1(1996-03-01), 67-70 1007-1202 1:1<67 1996 1 11859 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer