Nobuyuki Ikeda

A three-view model for developing object-oriented frameworks

This paper describes a three-view model for developing object-oriented frameworks. We propose a new methodology based on this model, and demonstrate its effectiveness using an example of practical industrial applications. This model can lead software engineers to a framework that has high reliability, portability, and maintainability. These quality factors of applications are especially important in a domain that has repeatability and changeability of hardware and software environment. The three-view model consists of a domain analysis view, a layer view, and a mechanism view. The domain analysis view is used to clarify all information and domain knowledge by using a new concept that we call Domain Reference Models (DRM), which reference models for modeling domain-specific objects, so that a framework has high reusability. The layer view is used to divide a framework into three layers that are piled up vertically: an infrastructure layer, a generic layer, and a domain layer. Because software engineers can replace a part of the framework for restriction on implementation, the framework has high portability. The mechanism view is used to decide which mechanism of whitebox frameworks or blackbox frameworks. By using this guideline, the framework has high maintainability. We applied our approach to the framework development for an industrial monitoring applications. By developing a prototype, we have a prospect of withdrawing the development costs of the framework by five or six times of application deployment. In this application, we estimate several ten times of application deployment. Therefore, it is effective for software engineers to develop a framework based on the three-view model.

Data Mining of Generalized Association Rules Using a Method of Partial-Match Retrieval

This paper proposes an efficient method for data mining of generalized association rules on the basis of partial-match retrieval. A generalized association rule is derived from regularities of data patterns, which are found in the database under a given data hierarchy with enough frequencies. The pattern search is a central part of data mining of this type and occupies most of the running time. In this paper, we regard a data pattern as a partial-match query in partial-match retrieval then the pattern search becomes a problem to find partial-match queries of which answers include sufficient number of database records. The proposed method consists of a selective enumeration of candidate queries and an efficient partial-match retrieval using signatures. A signature, which is a bit sequence of fixed length, is associated with data, a record and a query. The answer for a query is fast computed by bit operations among the signatures. The proposed data mining method is realized based on an extended signature method that can deal with a data hierarchy. We also discuss design issues and mathematical properties of the method.

Applying object-oriented technology to embedded software

The results and new technology proposal of applying object-oriented technologies to embedded control software are discussed in this paper. The following obstacles exist when we apply object-oriented technologies to embedded control software: (1) the analysis and design method for control algorithms and the method of reusing them as software components, and (2) the size reduction method limiting the advantages of object-oriented technologies. We propose solutions for each of them. First, we extend the usual object-oriented analysis method; the object structures are identified based on the structure of the control algorithms. Second, we give a hierarchical implementation architecture on small microcomputers. We use assembly language at the lower level of this architecture, and the use of the C++ language is restricted to the upper level. We show this mixed use of an object-oriented language with assembly language gives the expected balance of productivity and performance.