As one approach, some mathematical formulations were developed in terms
of mathematical programming models, which were aimed to construct the
minimum cost mutual parts supply system in the ASEAN region (Katayama et
al., 1993; Katayama and Hiraki, 1995; Katayama and Hiraki, 1996). This
research considers major cost issues such as production costs of specific parts
in each country, transportation costs and the tariff being paid for import/export
operations etc.