Research On Rough Set Model Based On Object-Oriented Database

Rough set theory is independent of any foregoing information which is excluded of processed data sets, and it is a new effective mathematic tool to deal with the uncertainty, imprecision and in completion. Since the end of 1980s, rough set has become hotspot gradually in the intellectual information processing field.Although traditional Rough set theory applications in data mining are almost based on structured method, it can possibly involve issues such as poor structural integrity of data model, low software reuse and lack of extensibility. Moreover, the systems based on rough set attribute reduction are mostly designed for a specific relational database or formatted data file. Therefore, it is difficult to describe complex objects and to meet the needs of research and application because of the lack of flexibility and versatility.To solve this problem, this paper combines object-oriented theory with rough set attribute reduction methodology to design an object model and an attribute reduction model, which can be viewed as an object-oriented attribute reduction model based on rough set. The experimental results show that the model not only effectively reduces the attribute of rough set, but also has the advantages of simple structure and good extensibility. In addition, the object model provided in this paper is also suitable for other data mining systems.The specific research work is listed:⑴The efficiency of the algorithm for attribution reduction in Rough Set based on main memory will be significantly reduced when dealing with larger data sets. To solve this problem, this paper proposes an algorithm for attribution reduction based on stored procedure, using the superiority of the database technology. The experimental results show that the efficiency of the algorithm is significantly higher than some other algorithms based on the main memory in dealing with large data sets. In addition, the algorithm can be easily realized, and has some practical value.⑵At present most of the attribute reduction algorithms use structured methods, but these methods are lack of unified data model. In view of this issue, the paper analyses the subjects of Rough Set using object-oriented theory and designs an Object Model for the attribute reduction, modeling it with object-oriented database DB4O.⑶This paper proposes a Rough Set Model based on the object-oriented database on the basis of the traditional Rough Set theory with the introduction of object-oriented databases.⑷A thorough discussion is given to the key technologies to achieve the attribute reduction algorithm. A professional data-processing software system, which is an attribute reduction system of Rough Set Model based on object-oriented database, is developed to verify the research results mentioned above.