A fuzzy expert system for qualitative chemical analyses of minerals using color recognition

The process relating to qualitative chemical analyses is based on sample analyses of minerals. Several considerations are performed by chemists, involving features such as hardness, luster, etc. Besides, solubility tests have a problem-how to determine suitable solvents to specific samples (based on color recognition). The process demands an expert knowledge and involves ponderations and cognitive inferences, peculiar to human reasoning. This kind of uncertainty is difficult to be modeled with traditional models. The color recognition is a complex process, because it is variable from observer to observer. The work proposes an expert system, based on fuzzy logic, which has a knowledge base structured using a classification tree with a membership function. To solve the color problem, the HSI method is used because of its similarity with the way humans observe colors