Development of next generation code system as an engineering modeling language, 5; Investigation on restructuring method of conventional code into two-layer system

Yokoyama, Kenji   

A proposed method for gradually restructuring to the two-level system of next generation analysis system by reusing the conventional analysis system, called "incremental method", was applied and evaluated. The following functions were selected for the evaluation of the restructuring: Neutron diffusion calculation for the three-dimensional XYZ system based on finite differential method, and input utilities of the cross-section data file. In order to evaluate the effect of the restructuring, "Module Coupling Index(MCI)" and "McCabe's Cyclomatic Complexity (MCC)" were used for quantifying the quality of the modular design and the complexity of the program sequence. The incremental method could reduce MCIs from 67 degrees to under 4 degrees in most module. And, it is found that the modules under 4 degrees of MCI can be easily combined with different programming languages. In the meantime, MCCs in most module before restructuring wereover 20 and some were over 50. The incremental method could reduce them to under 10 in most module. It is correspondent to reduction of the error frequency from 2040% to 510%. The total number of MCC was able to be reduced to 1/2. By using the restructured functions in the present study and some previously developed functions, a reactor analysis tool was systematized and applied to criticality analysis of the Experimental Fast Reactor "JOYO" MK-I. In addition, it is confirmed that additional functionality expansions were carried out satisfying the condition that one can extend it only with input data and functions fornormal users (the user extendibility) and one can extend it without any modifications of existing programs (the open-closed principle).