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Pattern supervised

In the meantime, USA in its mining industry possesses rigorous safety supervision and law enforcement system. The key of its success is represented in up-to-down coalmine safety supervision framework, rotational supervision personnel system, thunder-patterned supervision and law enforcement force. Furthermore, in the structure of the mechanism, a community of interest including the supervisors, mine operators and local governments is avoided. [Pg.694]

J. R. Whiteley andj. F. Davis, "QuaHtative Interpretation of Sensor Patterns using a Similarity-Based Approach," paper presented at the IFAC Symposium on On-Eine Fault Detection and Supervision in the Chemical Process Industries, Newark, Del., Apr. 1992. [Pg.541]

Mathematically, this means that one needs to assign portions of an 8-dimensionaI space to the three classes. A new sample is then assigned to the class which occupies the portion of space in which the sample is located. Supervised pattern recognition is distinct from unsupervised pattern recognition. In the latter one applies essentially clustering methods (Chapter 30) to classify objects into classes that are not known beforehand. In supervised pattern recognition, one knows the classes and has to decide in which of those an object should be classified. [Pg.207]

Supervised pattern recognition techniques essentially consist of the following steps. [Pg.207]

This is the simplest possible type of neuron, used here for didactic purposes and not because it is the configuration to be recommended. Let us suppose that for this isolated neuron w, = 1, Wj = 2 and 7=1. The line in Fig. 33.20 then gives the values of x, and Xj for which E = 7. All combinations of x, and Xj on and above the line will yield E > 7 and therefore lead to an output y, = 1 (i.e. the object is class K), all combinations below it toy, = 0. The procedure described here is equivalent to a method called the linear learning machine, which was one of the first supervised pattern recognition methods to be applied in chemometrics. It is further explained, including the training phase, in Chapter 44. [Pg.234]

Neurons are not used alone, but in networks in which they constitute layers. In Fig. 33.21 a two-layer network is shown. In the first layer two neurons are linked each to two inputs, x, and X2- The upper one is the one we already described, the lower one has w, = 2, W2 = 1 and also 7= 1. It is easy to understand that for this neuron, the output )>2 is 1 on and above line b in Fig. 33.22a and 0 below it. The outputs of the neurons now serve as inputs to a third neuron, constituting a second layer. Both have weight 0.5 and 7 for this neuron is 0.75. The output yfi j, of this neuron is 1 if E = 0.5 y, + 0.5 y2 > 0.75 and 0 otherwise. Since y, and y2 have as possible values 0 and 1, the condition for 7 > 0.75 is fulfilled only when both are equal to 1, i.e. in the dashed area of Fig. 33.22b. The boundary obtained is now no longer straight, but consists of two pieces. This network is only a simple demonstration network. Real networks have many more nodes and transfer functions are usually non-linear and it will be intuitively clear that boundaries of a very complex nature can be developed. How to do this, and applications of supervised pattern recognition are described in detail in Chapter 44 but it should be stated here that excellent results can be obtained. [Pg.234]

Most of the supervised pattern recognition procedures permit the carrying out of stepwise selection, i.e. the selection first of the most important feature, then, of the second most important, etc. One way to do this is by prediction using e.g. cross-validation (see next section), i.e. we first select the variable that best classifies objects of known classification but that are not part of the training set, then the variable that most improves the classification already obtained with the first selected variable, etc. The results for the linear discriminant analysis of the EU/HYPER classification of Section 33.2.1 is that with all 5 or 4 variables a selectivity of 91.4% is obtained and for 3 or 2 variables 88.6% [2] as a measure of classification success. Selectivity is used here. It is applied in the sense of Chapter... [Pg.236]

D. Coomans and D.L. Massart, Alternative K-nearest neighbour rules in supervised pattern recognition. Part 2. Probabilistic classification on the basis of the kNN method modified for direct density estimation. Anal. Chim. Acta, 138 (1982) 153-165. [Pg.240]

J.D.F. Habbema, Some useful extensions of the standard model for probabilistic supervised pattern recognition. Anal. Chim. Acta, 150 (1983) 1-10. [Pg.240]

The LLM is a classical supervised pattern recognizer. It tries to find boundaries between classes. In Fig. 44.3 an example of two classes A and B is shown in two dimensions (x, and Each possible object is thus defined by its values on x, and X2- The boundary between the two classes A and B is defined by the line, L, described by eq. (44.1) ... [Pg.653]

In preparation for a registration submission, applicants should conduct a residue study on each edible crop through supervised field trials. Residue data should be prepared for each use pattern and formulation type to be labeled. [Pg.42]

The knowledge required to implement Bayes formula is daunting in that a priori as well as class conditional probabilities must be known. Some reduction in requirements can be accomplished by using joint probability distributions in place of the a priori and class conditional probabilities. Even with this simplification, few interpretation problems are so well posed that the information needed is available. It is possible to employ the Bayesian approach by estimating the unknown probabilities and probability density functions from exemplar patterns that are believed to be representative of the problem under investigation. This approach, however, implies supervised learning where the correct class label for each exemplar is known. The ability to perform data interpretation is determined by the quality of the estimates of the underlying probability distributions. [Pg.57]

Blood pressure, health history, weight, digestive disorders, hunger, excretory patterns, stress and emotional health were all factors that were monitored with the 112 supervised clients. Most participants followed the program for seven days, and several requested to follow it a few days longer. [Pg.42]

Classical supervised pattern recognition methods include /( -nearest neighbor (KNN) and soft independent modeling of class analogies (SIMCA). Both... [Pg.112]

Next, supervised-learning pattern recognition methods were applied to the data set. The 111 bonds from these 28 molecules were classified as either breakable (36) or non-breakable (75), and a stepwise discriminant analysis showed that three variables, out of the six mentioned above, were particularly significant resonance effect, R, bond polarity, Qa, and bond dissociation energy, BDE. With these three variables 97.3% of the non-breakable bonds, and 86.1% of the breakable bonds could be correctly classified. This says that chemical reactivity as given by the ease of heterolysis of a bond is well defined in the space determined by just those three parameters. The same conclusion can be drawn from the results of a K-nearest neighbor analysis with k assuming any value between one and ten, 87 to 92% of the bonds could be correctly classified. [Pg.273]


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See also in sourсe #XX -- [ Pg.207 , Pg.652 ]




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