Hiroki Nogawa Yoshikazu Nakajima Yoshinobu Sato Shinichi Tamura Acquisition of Symbolic Description from Flow Fields: A New Approach Based on a Fluid Model. 58-63 1997 19 IEEE Trans. Pattern Anal. Mach. Intell. 1 http://doi.ieeecomputersociety.org/10.1109/34.566811 db/journals/pami/pami19.html#NogawaNST97