[mathematical modeling] differential equation -- sustainable development of fishing industry

The problem background

Renewable resources should be moderately developed ------- Achieve maximum output or best benefit on the premise of continuous and stable production

Problems and analysis

• stay The catch is stable Under the premise of , How to control fishing to maximize production or maximize benefits ？
• If the catch is equal to the natural increase , The amount of fish in the fishing ground will remain unchanged , The catch is stable .

Yield model

Equilibrium point and stability of first order differential equation

direct method , Do not solve the judgment x0 The method of stability

Yield model （ First, the output is stable –> Solve the maximum output ）

Benefit model （ The catch is stable –> Maximum benefit of solution ）