Use of experts

Experts may be utilized to supplement in-house capabilities especially in the applications of specialized inspection techniques, and in the areas of interpretation of inspection and test results. These may be engineers or scientists working in the nuclear industry, research and regulatory organizations which have knowledge and experience in nuclear research reactor performance and behaviour, or specialists from outside the nuclear industry. 

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Implementation of advanced performance degradation models, necessitate the inclusion of advanced instrumentation and sensors such as pyrometers for monitoring hot section components, dynamic pressure transducers for detection of surge and other flow instabilities such as combustion especially in the new dry low NO combustors. To fully round out a condition monitoring system the use of expert systems in determining fault and life cycle of various components is a necessity. 

Reference to such documents may be useful at early stages in the task analysis to inform the analyst about the overall nature and breadth of tasks carried out. Later, as the detail of the task is becoming established, such documents serve to provide crucial information. The use of experts in helping with the interpretation of documents is usually necessary, vmless the analyst is directly involved with the system on a regular basis. 

A number of commercial expert systems have been applied to screen drug libraries. For instance, DEREK, TOPKAT, MultiCASE, and many other systems all have possibilities in this regard. However, it should be noted that for broad screening only compounds with toxicity associated with them can be identified, and hence these are very crude measures of hazard assessment. The use of expert systems to screen libraries is fraught with dangers, not least that no performance statistics are available for these systems being used for such an application. It is also highly probable that the vast majority of predic-... 

The first recorded reference to the use of expert systems in pharmaceutical product formulation was in the London Financial Times in the spring of 1989 [3], closely followed by an article in the autumn of the same year [4], Both referred to the work then being undertaken by personnel at ICI Pharmaceuticals, UK (now AstraZeneca) to develop an expert system for formulating pharmaceuticals ab initio. Since that time several companies and academic institutions have reported their experiences. 

Other more mathematical techniques, which rely on appropriate computer software and are examples of chemometrics (p. 33), include the generation of one-, two- or three-dimensional window diagrams, computer-directed searches and the use of expert systems (p. 529). A discussion of these is beyond the scope of this text. 

Nevertheless, where it is difficult for a computer to learn expert system rules, the traditional expert system still has a place. A typical recent example of the use of expert systems is provided by the work of Dobrzanski and Madejski62 who have developed a prototype system for determining metal coating that provides an optimum combination of appearance, abrasion resistance, color, and other factors. A less scientific, but still intriguing, example of the use of these systems is HuskEval, an expert system for evaluating the quality of Siberian Huskies.63... 

The case study from chapter 7 is concerned with the design and improvement of chemically-active ship bottom paints known as antifouling paints. A hybrid experiment-model based approach is employed here. Experiments and use of expert knowledge are employed to identify product alternatives, whose evaluation in terms of performance as a marine biofouling protector is verified through a model-based approach. 

Reach target metabolic behavior, in particular target rate of activation Fast in vitro metabolic assessment and use of expert systems Dubious extrapolation to in vivo situations limited predictive capacity of some expert systems... 

The Use of Expert Systems for Toxicity Prediction Illustrated with Reference to the DEREK Program... 

The use of expert systems for toxicity prediction is based upon the premise that the activity of a molecule in any particular biological system is determined by its physicochemical properties, in particular its molecular structure (Barratt, 2000 Barratt and Rodford, 2001 Richard et al., 2000). From a knowledge of the latter, structural alerts — structural parts of molecules that are responsible for or can modulate biological activity, can be identified. 

Figure 9.5 Development and integrated use of expert systems tor toxicity prediction. 

There is widespread acknowledgment that it is extremely difficult to predict BCF values accurately for very hydrophobic compounds. Macdonald et al. (2002) have commented that for compounds with log Kow values greater than about 6, fitting any equation in this region is very adventurous. For compounds with log Kow > 8, they recommend the use of expert judgment. 

In this chapter the third level of computer-assisted HPLC—the use of expert systems (like Drylab [1], AutoChrom [2], and ChromSword [3]) for effective method development— is discussed. 

A clinical and legal issue of some importance is posed by the necessity for pupillary dilation. If there is litigation, the use of expert testimony is required to determine whether dilation was needed to conform to the standard of care in a specific instance. If a reasonable practitioner would maintain that a dilated fundus examination was necessary under the circmnstances, then the patient must receive that evaluation or be referred to another practitioner so that it can be performed. There are numerous... 

In classifying mixtures in this category, the use of expert judgment that considers surface tension, water solubility, boiling point, volatility is critical and especially when Category 2 substances are mixed with water. 

Techniques that may be used in making decisions lelated to pollution control aie briefly discussed. A hierarchy of objectives is a convenient way to structure the problem. The decision analysis includes valuation of effects which will depend on social values and attitudes in the society. The uncertainties in several steps of the analysis will normally be considerable the mryor uncertainty is often in the dose-response relationships. The use of expert panels to obtain such relationships is discussed. Finally an ongoing study of costs and benefits of control options for ait pollution in Oslo is used as an illustration. 

Mosleh, A., Bier, V. M., and Apostolakis, G A critique of current practice for the use of expert opinion in probabilistic risk assessment. Reliab. Eng. Syst. Saf. 20, 63 (1988). 

Qualitative Estimation Methods. Qualitative techniques have also been used to conduct or refine exposure reconstructions. The use of exposure determinants to classify exposures is a technique that has been performed qualitatively in some cases based on available data. Other qualitative techniques can include the use of expert or professional judgment and self-reported exposures. While self-reported exposures have been found to be convenient and helpful when no other exposure information is available, the method has been shown in at least one validation study to be inadequate for use as the sole data source in an exposure reconstruction. When self-reported exposures have been compared to professional judgments by experts, they have been found to have high specificity but low sensitivity (Fritschi et al. 1996). 

Walker, K. D., Catalano, R, Hammitt, J. K., and Evans, J. S. (2003). Use of expert judgment in exposure assessment Part 2. Calibration of expert judgments about personal exposures to benzene. J Expo Anal Environ Epidemiol 13, 1-16. 

Third, the developer must determine that the problem is well suited to use of expert system technologies. If the problem is purely algorithmic or procedural in nature, then it can be addressed by conventional technologies more efficiently than by expert systems. If the type of problem requires symbolic reasoning, then the problem may be suitable for expert systems technology. 

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