Recently, as business problems become more complicated and require more precise quantitative results, the analytical models for supporting the decision-making activities are increasingly in demand. The productivity and applicability of the models can be improved by utilizing composite models constructed by combining pre-existing models that have been operating. Meanwhile, as model management systems are employed in a distributed computing environment, the component models that construct a composite model can be scattered over heterogeneous distributed systems. Thus, we need to be able to construct a composite model using component models that are implemented separately and operate independently in heterogeneous distributed systems. Moreover, any changes occurred in a component model should not obstruct the proper operation of whole composite model. Therefore, it is desirable that the reflection of the component model’s change to a composite model is performed without any additional modification or re-compiling of the entire model management systems.
To satisfy such requirements, this paper proposes an object-oriented framework for facilitating a composite model construction using distributed object technology. By defining a model as an object and using the distributed object technology that supports mechanisms for interaction between objects, we can combine individual models to construct a composite model regardless of the platforms or the locations of the component models. In developing the framework, we propose a mechanism that separates the interface of a model from the implementation, and define an abstract composite model to manage the information that which component models are used and how their interfaces are linked in a composite model. Thus, changes of a component model implementation do not affect the other parts of the composite model. Additionally, to show the applicability of the proposed framework, we implement a prototype model management system using the popular distributed object technology, DCOM (Distributed Component Object Model) and C++ programming language on Windows NT platform.
