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Rule-based method

The descriptions such as¡Ö(It takes effect on neuralgia)¡×, ¡Ö(There is an open-air bath)¡× appear frequently in the pages about hot-springs. The expression ``'' means a pain and the expression ``''means a bath in Japanese. Then we use rules based on expression patterns and phrases like the above examples.

The process of describing extraction rules is twofold.

1. Definition of attributes

   A specific item to extract is defined as an attribute of a class in the ontology. For instance, attributes such as name, style, ingredient, effects are defined to extract information related with hot-spring.

   Figure 8 shows the definition of hot-spring attributes. This formula means that (hot-spring) has the attribute called (name) which take one value, the attributes such as (style), (ingredient) and (effects) which take some values, and it is a (a tourist resort).

   

   

2. Describing extraction rules based on specific expression patterns

   Figure 9 shows the rules to extract effects of hot-springs. The first rule means that if the expression pattern ``(effect)'' or ``(effective)'' appears with the concept (sickness and injury) in the same sentence, the pattern matching the concept indicates (effects). The second rule means that the expressions patterns ``+''or``+''or``+'' turns out in the sentence, the pattern indicates the concept (sickness and injury). Here, the symbol ``+'' holds the same meaning regular expression. For example, the expression ``+(pain)' matches ``(arthralgia)'', ``(lumbago)'' and so on.