tailieunhanh - Báo cáo hóa học: "Research Article The LOST Algorithm: Finding Lines and Separating Speech Mixtures"

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 The LOST Algorithm: Finding Lines and Separating Speech Mixtures | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 784296 17 pages doi 2008 784296 Research Article The LOST Algorithm Finding Lines and Separating Speech Mixtures Paul D. O Grady1 and Barak A. Pearlmutter2 S 1 Complex and Adaptive Systems Laboratory University College Dublin Belfield Dublin 4 Ireland 2 Hamilton Institute National University of Ireland Maynooth Co. Kildare Ireland Correspondence should be addressed to Paul D. O Grady Received 26 November 2007 Revised 3 April 2008 Accepted 2 July 2008 Recommended by S. Makino Robust clustering of data into linear subspaces is a frequently encountered problem. Here we treat clustering of one-dimensional subspaces that cross the origin. This problem arises in blind source separation where the subspaces correspond directly to columns of a mixing matrix. We propose the LOST algorithm which identifies such subspaces using a procedure similar in spirit to EM. This line finding procedure combined with a transformation into a sparse domain and an L1-norm minimisation constitutes a blind source separation algorithm for the separation of instantaneous mixtures with an arbitrary number of mixtures and sources. We perform an extensive investigation on the general separation performance of the LOST algorithm using randomly generated mixtures and empirically estimate the performance of the algorithm in the presence of noise. Furthermore we implement a simple scheme whereby the number of sources present in the mixtures can be detected automatically. Copyright 2008 P. D. O Grady and B. A. Pearlmutter. 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. 1. INTRODUCTION When presented with a set of observations from sensors such as microphones the process of extracting the underlying sources is .