the pupose of this paper is modeling of partial digest problem (pdp) as a mathematical programming problem. in this paper we present a new viewpoint of pdp. we formulate the pdp as a continuous optimization problem and develope a method to solve this problem. finally we constract a linear programming model for the problem with an additional constraint. this later model can be solved by the simp...

In this paper, developed a new multi-product, multi-period, and multi-level closed-loop green supply chain planning model under uncertain conditions. The formulated model consists of five objective functions, which minimize the cost of the supply chain, minimize the CO2 emission of transportation vehicles, maximize the reliability of manufacturing and distribution centers, maximize t...

in this article, a finite horizon, multi product and multi period economic order quantity like seasonal items is considered where demand rate is deterministic and known but variable in each period. the order quantities of items come in batch sizes and the end of the period order quantity and, consequently, demand of customers are zero. in addition, storage space is constrained and the problem ...

This paper presents three mathematical models for network design of cellular networks. The models reflect varying degrees of complexity. Model #1 is a 1-period fixed-link capacity model. Three heuristics are used for solving this problem. All the heuristics first use linear programming relaxations to yield the near-optimal integer solution, then use then clever rounding-schemes to find the fina...

Due to the importance of supplier selection issue in supply chain management (SCM) and ,also,  the increasing tendency of organizations to their social responsibilities, In this paper, we survey the supplier selection issue as a multi objective problem while considering the factor of corporate social responsibility (CSR) as a mathematical parameter. The purpose of this paper is to design a mode...