Mohammad Saeidi Mehrabad - Associate Professor
Mir-Bahador Aryanezhad - Professor
Maryam Esmaeili - The Student of Phd in Social & Economical Systems, IUST
Mehdi Abbasi - Assistant Professor of Shiraz Azad University

Considering the decision making in two separated parts, production and marketing causes reducing the efficiency of a firm and/or contrast in the way of doing what a company should do. With respect to relationship between production and market ,an integration or coordination model for production planning and marketing in order to maximize the benefit of a producing company will be offered. Production cost is a exponential function of production volume and demand is a exponential function of price and marketing expenditure and discount with elasticity coefficients. Considering the form of demand and cost ,the offering model is a signomial geometric programming. The constraint of model is the demand as the upper bound of the production volume. Using the Geometric programming for solving the problem, the optimizing amount of price , marketing expenditure, production lot size, production volume and discount. for each product will be determined. Then the numerical example, the upper and lower bound of objective function, sensitivity analysis and the effects of underestimation and overestimation amount will be told and at the end of paper, the conclusion and the suggestions are offered.

Convex programming, Geometric programming (GP), The signomial and posynomial geometric programming (Signomial and Posynomial GP), Joint manufacturing-marketing decisions, Optimization