Accession Number : ADA181378
Title : Processing Waveforms as Trees for Pattern Recognition.
Descriptive Note : Technical rept.,
Corporate Author : RICE UNIV HOUSTON TX DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
Personal Author(s) : Shaw,Scott W ; DeFigueiredo,Rui J
PDF Url : ADA181378
Report Date : May 1986
Pagination or Media Count : 63
Abstract : Waveforms may be represented symbolically such that their underlying, global structural composition is emphasized. One such symbolic representation is the relational tree. The relational tree is a computer data structure that descirbes the relative size and placement of peaks and valleys in a waveform. Researchers have developed various distance measures which serves as tree metrics. A tree metric defines a tree space. We are able to cluster groups of tree by proximity in tree space. Linear discriminants are used to reduce vector space dimensionality and to improve cluster performance. A tree transformation operating on a regualr tree langauge accomplishes this same goal in a tree space. Under certain restrictions, relational trees form a regular tree language. Combining these concepts yields a waveform recognition system. This system recognizes waveforms even when they have undergone a monotonic transformation of the time axis. The system performs well with high signal to noise ratios, but further refinements are necessary for a working waveform interpretation system.
Descriptors : *PATTERN RECOGNITION, *WAVEFORMS, CLUSTERING, TREES, COMPUTERS, DATA BASES, GLOBAL, DISCRIMINATE ANALYSIS, LINEAR SYSTEMS, SIZES(DIMENSIONS), LANGUAGE, RANGE(DISTANCE), SIGNALS, SIGNAL TO NOISE RATIO, TRANSFORMATIONS, VECTOR SPACES, DATA PROCESSING
Subject Categories : Cybernetics
Distribution Statement : APPROVED FOR PUBLIC RELEASE