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Pattern recognition problem

The general invariant pattern recognition problem is to construct a system which takes as input an element/of V and computes a value s(f), with the intention that s(f) = c(f) for all f V. [Pg.182]

Numeric-to-symbohc transformations are used in pattern-recognition problems where the network is used to classify input data vectors into specific labeled classes. Pattern recognition problems include data interpretation, feature identification, and diagnosis. [Pg.509]

For solving the pattern recognition problem encountered in the operation of chemical processes, the analysis of measured process data and extraction of process trends at multiple scales constitutes the feature extraction, whereas induction via decision trees is used for inductive... [Pg.257]

B. Waiczack and D.L. Massart, Application of radial basis functions-partial least squares to non-linear pattern recognition problems diagnosis of process faults. Anal. Chim. Acta, 331 (1996) 187-193. [Pg.698]

From both a theoretical and practical view, it is ideal to use Bayesian Decision Theory because it represents an optimal classifier. From a theoretical perspective, Bayesian Decision Theory offers a general definition of the pattern recognition problem and, with appropriate assumptions, it can be shown to be the basis of many of the so-called non-PDF approaches. In practice, however, it is typically treated as a separate method because it places strong data availability requirements for direct use compared to other approaches. [Pg.56]

Because of their ability to classify complex data types that have no explicit mathematical model, neural networks have become a powerful and widely used approach to pattern recognition problems in general. A neural network is a series of mathematical operations performed on input data that ultimately... [Pg.155]

The hypothesis of a normal distribution is a strong limitation that should be always kept in mind when PCA is used. In electronic nose experiments, samples are usually extracted from more than one class, and it is not always that the totality of measurements results in a normally distributed data set. Nonetheless, PCA is frequently used to analyze electronic nose data. Due to the high correlation normally shown by electronic nose sensors, PCA allows a visual display of electronic nose data in either 2D or 3D plots. Higher order methods were proposed and studied to solve pattern recognition problems in other application fields. It is worth mentioning here the Independent Component Analysis (ICA) that has been applied successfully in image and sound analysis problems [18]. Recently ICA was also applied to process electronic nose data results as a powerful pre-processor of data [19]. [Pg.156]

Figure 4. Available Data in the Pattern Recognition Problem Form a Matrix of Dimensions M Times N. Figure 4. Available Data in the Pattern Recognition Problem Form a Matrix of Dimensions M Times N.
The general pattern recognition problem can be described as follows. The input data, or pattern X, is defined by a number of specific data measurements, x, defined at a particular point in time ... [Pg.2]

Similarity/dissimilarity obviously plays an important role in all pattern recognition problems. The vagueness of this term itself suggests that there are numerous ways in which the dissimilarity D of two objects a and b may be defined, depending on the actual problem. Segmentation of molecular... [Pg.236]

Bandemer considered the role of fuzzy set theory in analytical chemistry. The applications they described focused on pattern recognition problems, the calibration of analytical methods,quality control, and component identification and mixture evaluation. Gordon and Somorjai applied a fuzzy clustering technique to the detection of similarities among protein substructures. A molecular dynamics trajectory of a protein fragment was analyzed. In the following subsections, some applications based on the hierarchical fuzzy clustering techniques presented in this chapter are reviewed. [Pg.348]

The major limitation of the simple perceptron model is that it fails drastically on linearly inseparable pattern recognition problems. For a solution to these cases we must investigate the properties and abilities of multilayer perceptrons and artificial neural networks. [Pg.147]

The fc-class pattern recognition problem with SVMs was initially solved by using one-against-the-rest and one-against-one classifiers. Recently, k-class SVMs have been proposed [324]. The optimization problem Eq. 3.79 is generalized to yield the decision function... [Pg.68]

Sensor array signal processing. As noted above, data from sensor arrays can be treated as a pattern recognition problem. Many types of traditional and novel approach have been explored for practicality and suitability. [Pg.382]

Neural nets are generally used where it is difficult to develop an analytical model such as in prediction or pattern recognition problems. Neural net models for corrosion prediction are an extension of empirical models. They too are not based on any theoretical background, with constants used in them representing best-fit parameters based on their training data set [1]. [Pg.384]

A currently popular approach to classification and pattern-recognition problems involves neural networks. Neural networks are mainly used as (non-)linear approximations to multivariable functions or as classifiers (Ripley, 1993). Principally, the technique is intended to mimic the computational properties of the brain, which is highly parallel in its operation. Artificial neural networks (Figure 3.10) consist of units with some of the properties of real neurons. [Pg.83]

The Philadelphia Arm of Taylor and Wirta (1970) and Taylor and Finley (1974) also never found clinical use, but like the Sven Hand found use as a research tool for multifunction control using weighted filters for the pattern recognition problem. The Belgrade hand too was never used clinically but has ended up in the robotics field in the form of the BelgradeAJSC robotic hand (Beattie et al., 1994). [Pg.854]

An example from chemistry may characterize a typical pattern recognition problem The objects may be chemical compounds and the property to be determined is the presence of a carbonyl group in the molecule. [Pg.2]

Basically, the TCM system can be achieved in a three-step procedure as a pattern recognition problem (Figure 4.1). Under this framework, the objective of TCM is to search the most probable state C, given the extracted measurable signal feature y(t) at time t. The sensor signal x t) is... [Pg.116]

In order to undertake database searches for a biomolecular system of interest, the creation of some form of binding model is essential. Generally, whereas a number of ligands for a given receptor may be known, the receptor structure itself may not be. In this instance, one must infer the critical small molecule—receptor interaaions from the data provided by the ligand structures. We now consider some of the many techniques used to solve this pattern recognition problem. [Pg.85]

A. I. Medalia and G. J. Hornik, "Pattern Recognition Problems in the Study of Carbonblack", Pattern Recognition. 1975 4, 155. [Pg.312]

Support vector classifiers [19] are commonly used because of several attractive features, such as simplicity of implementation, a small number of free parameters to be tuned, the ability to deal with high-dimensional input data and good generalization performance on many pattern recognition problems. [Pg.272]

Biometric system performs matching in pattern recognition problems between the training and test dataset for unknown features which would later determine the class (identity) of these unknown features. As a result of this learning technique, individuals can be identified for security and privacy purposes. [Pg.477]


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Pattern recognition

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