Research On Fleet Planning Of General-purpose And Special-purpose Dry Bulk Carriers With Uncertain Demand

At present,the shipping market is in a stage of overcapacity over demand and shipping surplus,especially the new crown epidemic that occurred in early 2020.The world’s dry bulk trade has shown a negative growth,which undoubtedly further aggravated the imbalance of supply and demand in the shipping market.Severe shipping market challenges,so how to make a scientific and timely fleet planning decision is of vital importance.Although the current fleet planning has formed a preliminary and complete theoretical system,most of the literature researched on a single type of cargo,which resulted in all ships being dedicated ships.In fact,there are not only Panamax dry bulk carriers and super handy types on the market.Bulk cargo ships,as well as special ships such as iron ore ships,coal ships,and grain ships.So this is different from the actual situation.This article draws on the relevant knowledge of fleet planning theory and uses whether it can transport a variety of goods to divide ships into two categories,general-purpose ships and special-purpose ships,and introduces the advantages and disadvantages of the two types of ships,and they can complement each other to cope with the market.Volatility on demand.This paper considers demand fluctuations in the market,analyzes various forms of robust optimization models,and finally adopts a robust optimization model based on scenario sets to construct a robust optimization model for dry bulk fleet planning.This model takes the minimum cost as the goal.And considering the investment capacity of the enterprise,through solving the model,not only how to purchase and lease ships in each period,but also give an example of the number of ships allocated on a route in a certain scenario,and verify the robustness of the solution of the robust optimization model through the objective function gap.The program has strong practicability,and helps shipping companies to have certain theoretical support and decision-making references when planning their fleet,better choose ship types and formulate future development strategies,and fully improve the competitiveness and resistance of the fleet.Risk capacity and operational flexibility.In addition,the sensitivity analysis under different risk parameters is also studied,the cost change trend under each parameter and the corresponding penalty cost change trend are analyzed,which reflects the robustness of the model to a certain extent.