GCLSC — Green Closed-Loop Supply Chain Network Design

Bi-objective mixed-integer linear programming model for designing a green closed-loop supply chain network for the tire remanufacturing industry under uncertainty — maximizing total profit while minimizing environmental impact.

Overview

The network spans customer and collection centers, recycling, manufacturing/remanufacturing plants, and distribution centers. Uncertainty is handled with the Jiménez fuzzy approach (experiment with different β levels), and two solution methods are combined:

• Augmented ε-constraint method in GAMS (BARON solver) for exact Pareto solutions
• Grasshopper Optimization Algorithm (GOA) in MATLAB for medium and large instances

The study includes numerical experiments and sensitivity analysis on both methods.

Repository structure

.
├── gams/
│   ├── Z1Function.gms              # single-objective run — total profit
│   ├── Z2Function.gms              # single-objective run — environmental impact
│   └── Test problem-Augmecon2.gms  # bi-objective test problem via AUGMECON2
├── matlab/
│   ├── GOA.m                       # Grasshopper Optimization Algorithm — main script
│   ├── CostFunction.m              # objective evaluation
│   ├── CreateModel.m               # problem instance definition
│   ├── CreateRandomSolution.m      # initial population
│   └── SocialInteraction.m        # GOA movement operator
└── LICENSE.txt

Getting started

GAMS (exact method)

1. Install GAMS with the BARON solver.
2. Open the files in gams/ and run the single-objective models first, then the AUGMECON2 test problem.

MATLAB (meta-heuristic)

1. Open matlab/ in MATLAB.
2. Adjust the instance in CreateModel.m if needed, then start from GOA.m.

Citation

This repository accompanies our paper in the Journal of Industrial and Systems Engineering:

@article{shahedi2021designing,
  title   = {Designing a green closed-loop supply chain network for the automotive tire industry under uncertainty},
  author  = {Shahedi, Tina and Aghsami, Amir and Rabani, Masoud},
  journal = {Journal of Industrial and Systems Engineering},
  volume  = {13},
  number  = {4},
  pages   = {226--261},
  year    = {2021}
}

📄 Read the paper

Related work

• Companion repository: GCLSC-CE — the same network with cannibalization effects (GAMS + Python NSGA-II).

License

Released under the GPL-3.0 License.