In order to realize exchange and share of something including information and knowledge, it should be needed for a provider and a user to arrive at same things and to recognize it. In some case the user may arrive the thing following his conceptual tree from root to leave, sometimes the user may hyper jump one branch to other. In other case the user may arrive the thing directly. According to his classification, the provider may locate his offerings in his conceptual space.

When we think about cooking as a concrete thing, it seems that there are various way a user can select a cooking. For example, the first case, the user may select a cooking from the view of ingredient like meet, fish, vegetable etc, the second case the user may select it from the view of country or area like Japanese cooking, Korean cooking, Chinese cooking, etc. And furthermore, a person who is caring about his health may select a cooking from the view of nutrient or a person who is not good health may select a cooking to fit his condition. On the other hand, it seems popular that a provider (a restaurant) provide a cooking in accordance with their menu and classifying and locating it in their context. Some kinds of restaurant may have a menu that is one-sided to specific cooking, another kinds of restaurant have a menu that cover wide range of cooking. It seems that the condition a cooking is selected is that a user and a provider identify and specify the same cooking.

We engaged in the catering service project of a self-governing body. In that project, we developed choice system of cooking using Topic Maps. From the user's and the provider's point of view, we classified the cooking (ontology) and created Topic Maps separately. In that we defined things (cooking) that the user and the provider could identify in common and use it to make Topic Maps as component. We used mergeMap function of Topic Map and also used the cooking as binding point of merge. As a result, the user was able to select the cooking and the provider from user's point of view (matchmaking of user and provider) without special matching mechanism. In this case it seems that the common things (cooking) can be defined as the Published Subject. As the result, Published Subjects become the binding points. Though in this project the common things were the cooking, it is possible to apply to another things.

Each user and provider creates Topic Map separately according to their ontology using same component, which are defined as the Published Subjects. Then they bring their Topic Maps into “common place” (market place) and merge all of them using mergeMap function of Topic Map. As a result locating the Published Subjects as binding points, the user and the provider can obtain matchmaking mechanism, which is personalized for each user and provider. We hope that eventually the knowledge and theory developed through this project will help bring new application of Topic Maps.