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Sensors in Flexible Manufacturing Systems
                          problem by hypothesizing massively parallel computers that can per-  399
                          form matching in linear time. Examples of these approaches include
                          graph matching, relaxation, and histogram analysis. The advantage
                          of these applications is that the decision is based on all the available
                          information at hand.
                             The basic principle of the  local-feature-focus (LFF) method is to
                          find one feature of an image, referred to as the focus feature, and use it
                          to predict a few nearby features to look for. After finding some nearby
                          features, the program uses a graph-matching technique to identify
                          the largest cluster of image features matching a cluster of object fea-
                          tures. Since the list of possible object features has been reduced to
                          those near the focus feature, the graph is relatively small and can be
                          analyzed efficiently.
                             The key to the LFF method is an automatic feature-selection pro-
                          cedure that chooses the best focus features and the most useful sets of
                          nearby features. This automatic-programming capability makes pos-
                          sible quick and inexpensive application of the LFF method to new
                          objects. As illustrated in Fig. 8.15, the training process, which includes
                          the selection of features, is performed once and the results are used
                          repeatedly.



































                          FIGURE 8.15  Runtime phase procedure.
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