Engine/rule separation

A more principled approach is to define a general rule format, a mle processor or engine and a clearly defined set of rules. This at least has the advantage of engine/rule separation meaning that the way the rules are processed and the rules themselves are separate, which helps with system maintenance, optimisation, modularity and e q)ansion to other languages. One common type of rule is the context-sensitive rewrite rule, which takes the form... 

Similarly, Overcash et al. [32] produced an engineering rule-of-practice-based analysis of separate unit processes used in manufacturing. The information is collated in the form of a unit process life cycle inventory, which then helps to evaluate the manufactured products through the quantification of various parameters, including input materials, energy requirements, material losses and machine variables. 

The different process units are sized according to general engineering rules [55] as well as by using simulations in the commercial process design package AspenPlus. It should be noted that the calculated sizes of the extractor and separator shown in Table 14.9 are relatively small as compared to the typical size of an industrial emulsion polymerization reactor (50 m ). 

The synthesis is carried out in two phases. In the first phase a heuristic starting routine is used to generate an initial tree. It was found through experience that the pipes connected to the separation plant (the root of the tree) play a special role in the development of a tree. These pipes will be referred to as arms and the pipes connected to each arm its subtree. It is assumed that the number and location of the arms are specified as program input by the engineer. The two heuristic rules used by the starting routine are (i) efficient trees have low total pipe mileage (ii) efficient trees have nearly equal flow in their arms. Notice that the application of rule (i) by itself... 

Environmental regulations prohibit disposal of produced water without primary and. in some instances, secondary treatment. Corrugated-plate interceptors, cross-flow separators, flotation units and other specialized equipment is required to reduce hydrocarbon content to acceptable levels. Authors discuss various equipment used in water treating. Next month, equations and empirical rules to help the engineer select appropriate treating equipment wilt be provided. 

Multiresponse experimentation is important in studies of complex systems and of systems observed by multiple methods. Chemical engineers and chemists use multiresponse experiments to study chemical reactions, mixtures, separation, and mixing processes similar data structures occur widely in science and engineering. In this chapter we study methods for investigating process models with multiresponse data. Bayes theorem now yields more general methods than those of Chapter 6, and Jeffreys rule, discussed in Chapter 5, takes increased importance. 

Heuristic methods were developed by well-experienced engineers and researchers. The first attempt to develop a systematic heuristic approach for the synthesis of multicomponent separation sequences was made by Siirola and Rudd. Common example is hierarchical heuristic approach.Heuristic rules are applied at five design levels to generate and evaluate the alternatives using economic criteria. The hierarchical heuristic method emphasizes the strategy of decomposition and screening. It allows for a quick location of flowsheet structures that are often near ... 

Quantity calculus, the manipulation of numerical values, physical quantities and units, obeys the ordinary rules of algebra.11 Combined units are separated by a space, e.g. J K 1 mol 1. The ratio of a physical quantity and its unit, Q/ Q, is a pure number. Functions of physical quantities must be expressed as functions of pure numbers, e.g. log(k/s 1) or sinfoj/). The scaled quantities Q/ Q are particularly useful for headings in tables and axis labels in graphs, where pure numbers appear in the table entries or on the axes of the graph. We will also make extensive use of scaled quantities Q/ Q in practical engineering equations. Such equations are very convenient for repeated use and it is immediately clear, which units must be used in applying them. For example, a practical form of the ideal gas equation is shown in Equation 1.2. 

These rules are ready to be run by an inference engine. The inference engine is a separate entity from the KEY system. In the present work, a rudimentary inference engine was written in Prolog to test the knowledge base that KEY generated. Each answer the inference engine provides is a result of the combination of certainty factors from several rules. 

A separate inference engine should be used to process the rule base, allowing for multiple inference strategies using the same rule base and providing easy rule modification. Additionally, the inference engine itself may be reused for other projects. 

---