Heuristic Knowledge

Fuzzy logic encodes human expert knowledge/heuristics, common sense, and the constraints are naturally enforced. 

This knowledge (heuristic nature) is the stored in the computer and users call upon the computer for specific advice as needed. The computer can make inferences and arrive at a specific conclusion. The expert systems powerful and flexible means for obtaining solutions to a variety of problems that often cannot be dealt with by other, more traditional and orthodox methods (ASHARAFI et al., 1995). 

DENDRAL followed a three-stage procedure. In the first phase, the so-called plan, prior knowledge, and heuristics were used to deduce a set of constraints. Constraints could be, for example, the exemption of large sets of candidate solutions or the suggestion for a extensive search over limited classes of solutions. 

Comas J, Rodriguez-Roda I, Sanchez-Marre M, Cortes U, Freixo A, Arraez J, Poch M (2003) A knowledge-based approach to the deflocculation problem integrating on-line, off-line, and heuristic information. Water Res 37(10) 2377-2387... 

The knowledge base of an expert system contains the relevant knowledge about the specific area of the expert system. For this all necessary heuristics must be... 

The knowledge base is a storehouse of facts, rules, and heuristics that relate to the domain in which the system provides advice. As far as possible, it contains everything that might be useful to the ES in solving problems. 

A broad class of optimization strategies does not require derivative information. These methods have the advantage of easy implementation and little prior knowledge of the optimization problem. In particular, such methods are well suited for quick and dirty optimization studies that explore the scope of optimization for new problems, prior to investing effort for more sophisticated modeling and solution strategies. Most of these methods are derived from heuristics that naturally spawn numerous variations. As a result, a very broad literature describes these methods. Here we discuss only a few important trends in this area. 

Also when resorting to heuristic rate equations or other approximative schemes, the construction of detailed kinetic models necessitates quantitative knowledge about the kinetic properties of the involved enzymes and membrane transporters. Notwithstanding the formidable progress in experimental accessibility of system variables, detailed in Sections IV and VI, for most metabolic systems such quantitative information is only scarcely available. 

The contents of a knowledge base, the facts and rules, or heuristics about a problem will be discussed shortly. The problem-solving and inference engine is the component of the system that allows rules and logic to be applied to facts in the knowledge base. For example, in rule-based expert systems, "IF-THEN" rules (production rules) in a knowledge base may be analyzed in two ways ... 

The Knowledge Base. The knowledge base holds symbolic knowledge. To be sure, the knowledge base can also contain tables of numbers, ranges of numerical values, and some numerical procedures where appropriate. But the major content consists of facts and heuristics. 

Computational efficiency. The efficiency of inference is enhanced by program and knowledge-base structure and by machine speed. Also, heuristic procedures, as used by experts, can augment the deductive procedures of conventional inference. 

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