MIP benchmarks for a beer game (Multi-echelon inventory management problem with four facilities) using Gurobi.
# Clone repo
git clone https://github.com/qihuazhong/multi-echelon-gurobi.git
cd multi-echelon-gurobi
# Install python dependencies
pip install -r requirements.txt
# Install multi-echelon-inventory environment
git clone -b dev-single-agent https://github.com/qihuazhong/multi-echelon-drl.git
# Run
python main.py --scenario basic --n-instances 10$$ \begin{aligned} \min \sum_{k\in K}\sum_{j\in J} &(C_{b}^{j}B_{k}^{j} + C_{h}^{j}I_{k}^{j})\ \ \text{Subject to:}\ I_{k-1}^{1}+E_{k-LS^{1}}^{2}-B_{k-1}^{1} &=d_{k}+I_{k}^{1}-B_{k}^{1},\forall k\in K\ I_{k-1}^{j}+E_{k-LS^{j}}^{j+1} &=E_{k}^{j}+I_{k}^{j},\forall k\in K,j\in J/{1}\ \sum_{t=1}^{k}E_{t}^{j} &=\sum_{t=1}^{k}P_{t-LI^{j-1}}^{j-1}-B_{k}^{j}+B_{0}^{j},\forall k\in K,j\in J/{1}\ B_{k}^{j},P_{k}^{j},I_{k}^{1} &\geq0,\forall j\in J,k\in K\ E_{k}^{j} & \geq0,\forall j\in J/{1},k\in K\ I^{j}{k} &\leq x^{j}{k}M, \forall j \in J, k \in {K}\ B^{j}{k} &\leq y^{j}{k}M, \forall j \in J, k \in {K}\ x^{j}{k} + y^{j}{k} &\leq 1, \forall j \in J, k \in {K}\ x^{j}{k}, y^{j}{k} &\in {0, 1} \forall j \in J, k \in {K}\ I^{j}{k}, B^{j}{k}, P^{j}{k}, E^{j}{k} &\geq 0, \forall j \in J, k \in K \end{aligned} $$
| Instance | Perfect_Info | iterative_MIP | once_MIP |
|---|---|---|---|
| 0 | -206.00 | -4,209.25 | -11,474.25 |
| 1 | -206.00 | -3,770.00 | -1,718.50 |
| 2 | -189.50 | -4,214.00 | -12,394.75 |
| 3 | -452.00 | -2,933.25 | -1,861.50 |
| 4 | -247.25 | -4,112.75 | -15,235.75 |
| 5 | -276.50 | -4,262.00 | -10,819.75 |
| 6 | -514.00 | -5,713.50 | -22,833.25 |
| 7 | -276.50 | -4,015.00 | -1,894.00 |
| 8 | -801.50 | -4,672.75 | -5,959.50 |
| 9 | -203.25 | -3,836.00 | -1,176.50 |