# Essay on Assigning Regions to Sales Representatives at Pfizer Turkey

Words: 2028
Pages: 9

25/12/2012

IE 251

Assigning Regions to Sales Representatives at Pfizer Turkey

Group Members:

TABLE OF CONTENTS

1. INTRODUCTION 3 2. WORK CONDUCTED IN CASE STUDY 3 3. Mathematical Model 5 4. SENSITIVITY ANALYSİS 6 5. CONCLUSİON 7 6. APPENDİX 8

1.
…show more content…
Xij is the assignment of ith brick to jth SR office. Yij is the current assignment of ith brick to jth SR office (Appendix Table 3) Di is the index values of ith brick (Appendix Table 2). Cij is the travel distances between jth SR office and ith brick (Appendix Table 1). The table of index value and travel distance is given us in case study. These tables can be seen in Appendix.
Obj. functions: Z1 is the min. total disruption function Z2 is the min. total travel distance between jth SR office and ith brick

Min. Z1=∑i=130 ∑5j=1 Di(Xij×(1- Yij))
Min .Z2=∑i=130 ∑5j=1 Xij× Cij + 0.000001× Z1
s.t. ∑30i=1 (Xij×Di) ≤ 1.2 for all j ∑30i=1 (Xij×Di) ≥0.8 for all j (Binary constrains) ∑5j=1 Xij =1 for all ith brick. Xij ≥ 0 for all i and j . Xij € {0,1} (integer constrain)

For part 1, part 2 we used these mathematical models.

In part 3 we add 10 different total disruption as a constrain which can be seen on Figure 3. Z1≤2,0447 | Z1≤1,86554 |