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Inference procedural

For the purposes of this paper, I will not describe the inference procedures further. I will also say very little about the human-machine interface. However, since expert systems are designed to be built by experts and used by experts and novices alike, the interface is of crucial importance. The examples discussed later illustrate how powerful interfaces are implemented through use of high resolution bit-mapped graphics, menu and "button"... [Pg.4]

An expert system is a computer program to reproduce a problem-solving manner according to an expert s knowledge and inference procedures in a computer system. Expert systems have been used for fault diagnosis in bioprocess operations, the improvement of medium composition, and the optimization of culture conditions, since it can handle a large amount of information and data concerning bioprocess operation and optimization [13]. [Pg.233]

Box and Meyer did not present any formal inference procedures for using this statistic to identify dispersion effects. The use seems to be informal for screening factors with large effects from those with no or small effects on dispersion, for example, by making a normal probability plot of the statistics see Montgomery (1990) for an application of this idea. [Pg.31]

Consider now robustness. If the estimators A are computed from independent response variables then, as noted in Section 1, the estimators have equal variances and are usually at least approximately normal. Thus the usual assumptions, that estimators are normally distributed with equal variances, are approximately valid and we say that there is inherent robustness to these assumptions. However, the notion of robust methods of analysis for orthogonal saturated designs refers to something more. When making inferences about any effect A, all of the other effects At (k i) are regarded as nuisance parameters and robust means that the inference procedures work well, even when several of the effects ft are large in absolute value. Lenth s method is robust because the pseudo standard error is based on the median absolute estimate and hence is not affected by a few large absolute effect estimates. The method would still be robust even if one used the initial estimate 6 of op, rather than the adaptive estimator 6L, for the same reason. [Pg.275]

EIAxpert rules allow invoking external models as part of the inference procedure. This includes models for impacts of reduced water flow, wastewater discharges. [Pg.266]

An expert system is an intelligent, computerized, knowledge-based system that uses symbolic processes and inference procedures to simulate the decision-making process that an expert performs to solve a problan. [Pg.1166]

An inference engine (or control structure) uses inference procedures to draw conclusions and to infer the correct control action based on the information stored in the knowledge base and the current state of the process. [Pg.1166]

A reliability model. The sequence of failures is modeled as a stochastic process. This model specifies the failure behavior process. The model parameters are determined by fitting a curve to failure data. This implies also a need for an inference procedure to fit the curve to data. The reliability model can then be used to estimate or predict the reliability (see Section IV). [Pg.318]

Calculate reliability. The inference procedure is applied on the failure data and the reliability model. Thus, a reliability estimate is produced. [Pg.319]

Nonparametric analysis provides powerful results since the rehahility calculation is unconstrained to fit any particular pre-defined lifetime distribution. However, this flexibility makes nonparametric results neither easy nor convenient to use for different purposes as often encountered in engineering design (e.g., optimization). In addition, some trends and patterns are more clearly identified and recognizable with parametric analysis. Several possible methods can be used to fit a parametric distribution to the nonparametric estimated rehability functions (as provided by the Kaplan-Meier estimator), such as graphical procedures or inference procedures. See Lawless (2003) for details. We choose in this paper the maximum likelihood estimation (MLE) technique, assuming that the sateUite subsystems failure data are arising from a WeibuU piobabihly distribution, as expressed in Equations 1,2. [Pg.868]

A complete data-generative process for MALDI-MS can be captured in a Bayesian framework [38, 39]. The preprocessing phase is then a Bayesian inference procedure where the Nx P table of interest is the mean of a posterior distribution given the observed signals. The computation involved in simulation of the posterior distribution is expensive, however, and dedicated modeling expertise is required for this approach. [Pg.415]

To speed up the inference procedure, a tree search is performed instead of a linear search while matching an observation to a regular expression. The tree search uses an automatically generated hierarchical search tree. The original archetypes form the leaves of the tree, while inner nodes are created based on the similarity between the activities based on the nine dimensions. [Pg.650]

Variability measures The likelihood functions and prior distributions have been incorporated in a Bayesian inference procedure in which the posterior density n 01E) is computed. The Bayesian inference is performed by using a Markov Chain Monte Carlo Method (MCMC), which allows samples to be generated from a continuous unnormaUzed density (Chiband Greenberg, 1995). The MCMC method, which is frequently applied to Bayesian Inference problems (Gilks et al. 1996), results in a m-samples set S = 0,. .., 0, representing the... [Pg.1306]

Several authors [8, 4, 9] have argued for the usefulness of estimating a probability of correctness. Voas and co-authors [8] argued that given a lower bound on the pfd that any one fault can produce ( testability ), one can infer from failure-free testing a probability of correctness. Bertolino and Strigini published the inference procedure for this case [10, 11] however, one cannot usually demonstrate a lower bound on the probability of failure it is hard to demonstrate experimentally that an event that is very unlikely to start with, and never observed, is actually impossible. Thus the treatment used here, producing a worst-case prediction without such assumptions, is a major step towards practical applicability. [Pg.112]

An inference system commonly used to develop fuzzy models is the Mamdani fuzzy inference system. The Mamdani approach was developed in the 1970s and was the first inference method applied to control systems [15]. The Mamdani inference procedure describes the output variables as fuzzy sets. The approach uses max-min composition in which the minimum of the two antecedents is taken for a particular rule and the maximum combination of the rules is determined for aggregating the effects of aU the rules. The effect of the max combiner on the output membership functions is to generate an "envelope" of the fired output membership functions. In order to defuzzify this output set, the centroid (weighted average) of the envelope is found by integrating over the 2-dimensional shape. The defuzzification process of the Mamdani approach is computationally intensive. [Pg.472]

If the have a trustworthy analytical description or an simulator at our disposal, then the problem of the optimum or an acceptable decision is reduced to some regressive models parameters estimation. Otherwise inductive inference procedures seem to be to the point. These are able to generate decisions outside the model, using minimum suppositions as to the parameters links pattern. Besides it is possible to construct an analytical description by inductive inference using fast analytical descriptors (regressive model selection). [Pg.97]

In the version "c [4] the inductive inference procedure is used for quick construction an analytical model, describing the links between the initial information and the condition of the studied object pareuneters set being analysed belonging to a certain class. [Pg.98]


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