This paper presents a new feature-based matching algorithm for tracking mesoscale precipitation phenomena in radar image sequences. Distinct rainfall areas are identified in each image and characterized by a feature v...
详细信息
This paper presents a new feature-based matching algorithm for tracking mesoscale precipitation phenomena in radar image sequences. Distinct rainfall areas are identified in each image and characterized by a feature vector of shape descriptors, which provide a mathematical representation of the spatial characteristics of each identified area. Rainfall areas observed in consecutive images are matched by comparing the relative values of the features. Two match scoring algorithms are developed to generate the initial estimates of correct matches, which are then updated by likelihood measures based on relative location. The method is applied to mesoscale rainfall areas observed in sequences of radar-derived images of rainfall activity over Southwestern Ontario during the summers of 1980 and 1981.
pattern recognition with unknown costs of classification is formulated as a problem of adaptively learning the optimal scheme starting from an ad hoc decision scheme. It is shown that unsupervised learning is adequate...
详细信息
pattern recognition with unknown costs of classification is formulated as a problem of adaptively learning the optimal scheme starting from an ad hoc decision scheme. It is shown that unsupervised learning is adequate to compute converging estimates of the mean values of the MN random classification costs, one for each combination of M classes and N decisions. The quantities required for estimation are 1) the decision taken, 2) the outcome of the cost random variable corresponding to the unknown class and the implemented decision, and 3) the a posteriori probabilities of all the classes. Some of the variations of the above learning scheme are discussed. An application of the proposed methodology for adaptively improving the performance of pattern-recognition trees is presented along with simulation results.
暂无评论