Trial Implementation Conceptual Schema Modelling Facility

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The results of this research are composed of the following three topics :(1) Trial Implementation of Conceptual Schema Modelling Facility (Single thread environment)(2) Trial Implementation of Conceptual Schema Modelling Facility (multi-thread environment)(3) Investigation of the standard specification of Conceptual Data Model(1) is the kernel of this research. We have implemented a data modelling facility where not necessarily finite meta data structure appears. The programming language used was Prograph and the obtained results are published in a symposium or as a paper in a book.(2) was to implement the similar modelling facility using object-oriented programming language, but we could not get the expectedresults. We tried the implementation using Macintosh, but the object-oriented platform SOM was not stable and we met a lot of troubles.At first, we tried object-oriented database Neo Access, but this package was very difficult to use and we have to change database tool in the middle of our project. Our implementation is a kind of DBMS where full uses of multi-threaded operationg system component were required and we could not take bugs whose causes were unknown.(3) Parrel to this research project, we proposed similar specification to the international standardization group, but we could not persuade experts who represented many nations. We have found that even if a specification is clearly stated, that is not enough to persuade many national bodies.It is important that the proposed specification must has some theoretical or objective properties (e.g.mathematics) that is unanimously admitted in the world. Therefore, we investigated the possibility to treat conventional data model by predicate calculus, and have found that a data model can be represented by a formula of predicate calculus. In logic, completeness or imcompleteness of the formula is well-known and we can persuade experts more easily.