... recognition and topic- word extraction", Proc. IEEE Int. Conf. Acoust., Speech, Signal Process., Phoenix, pp. 625-628 (1999) [6] M. Witbrock and A. G. Hauptmann: "Speech recognition and ... cepstral parameters and their regression coefficients as speech features, triphone HMMs as acoustic models, vocabularies of several thousand or several ten thousand entries, and stochastic language ... company and with the SNCF (the French Railways), LIMSI has developed a prototype telephone service providing timetables, simulated fares and reservations, and information on reductions and services...