| Unit cost of manufacturing a new product. |
| Unit cost of remanufacturing a used product into a new product |
| Unit cost of collecting and handling a returned unit |
| The return rate. |
| The scaling parameter. |
| Unit wholesale price of a new product. |
| Unit retail price of a new product. |
| The cost of green innovation investment parameter. |
| The demand of new products in the market, where
|