Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Formant Frequencies under Cognitive Load: Effects and Classification | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2011 Article ID219253 11 pages doi 2011 219253 Research Article Formant Frequencies under Cognitive Load Effects and Classification Tet Fei Yap 1 2 Julien Epps 1 2 Eliathamby Ambikairajah 1 2 and Eric H. C. Choi EURASIP Member 2 1 School of Electrical Engineering and Telecommunications The University of New South Wales Sydney NSW2052 Australia 2 ATP Research Laboratory National ICT Australia NICTA Eveleigh NSW 2015 Australia Correspondence should be addressed to Tet Fei Yap Received 1 August 2010 Accepted 20 December 2010 Academic Editor Shrikanth Narayanan Copyright 2011 Tet Fei Yap et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Cognitive load measurement systems measure the mental demand experienced by human while performing a cognitive task which is useful in monitoring and enhancing task performance. Various speech-based systems have been proposed for cognitive load classification but the effect of cognitive load on the speech production system is still not well understood. In this work we study formant frequencies under different load conditions and utilize formant frequency-based features for automatic cognitive load classification. We find that the slope dispersion and duration of vowel formant trajectories exhibit changes under different load conditions slope and duration are found to be useful features in vowel-based classification. Additionally 2-class and 3-class utterance-based classification results evaluated on two different databases show that the performance of frame-based formant features was comparable if not better than baseline MFCC features. 1. Introduction Cognitive load refers to the load imposed by a certain task on the cognitive system of a person 1 . .
