Green shipping oriented waste disposal optimization for cruise ships under stochastic context

Abstract

The rapid development of the cruise industry has brought a series of marine environmental problems. In the process of cruise navigation, cruise operation and passengers on board will produce an uncertain amount of waste. Generally, the total amount of waste is far greater than its capacity. It is necessary to dispose of waste in multiple ports of the line, which requires a certain fee to be paid to the port. Therefore, this paper studied a waste disposal problem for cruise ships to decide which port to sign and how much waste should be discharged under the uncertain amount of produced waste. These decisions affect the operating costs of cruise companies, so it is necessary to calculate and analyze scientifically through some optimization models. Based on the theory of system engineering, this paper analyzed the background of the above-mentioned decision-making problems and proposed three models successively by using the theory and tools of mathematical programming. The models include a deterministic model, a stochastic programming model that applied to arbitrary probability distributions of emission parameters, and a three-stage robust optimization model that can cope with the uncertain parameter interval. Then, considering the above problems and the characteristics of the model, this paper designed a Tabu search (TS) and particle swarm optimization (PSO) algorithms to solve large-scale problems in stochastic and robust models, respectively. Extensive experiments in this paper validated the effectiveness and efficiency of the proposed models and algorithms. The decision-making method of cruise waste emissions proposed in this paper has certain application value and guiding significance for the development of the current global green shipping industry. 邮轮产业的蓬勃发展带来了一系列的海洋环境问题，邮轮运营及船上乘客皆会产生不定量的废弃物，通常废弃物总量远大于其承载容量，需要在航线的多个港口处理废弃物并向港口缴纳一定费用。因此，与哪些港口签订长期合同，在哪个港口排放多少废弃物等决策将会影响邮轮公司的运营成本；这些决策需要通过一些优化模型进行科学地计算和分析。本文基于系统工程的思维对上述决策问题背景进行了分析，并运用数学规划的理论与工具，先后构建了确定性模型、适用于排污量参数服从任意概率分布的随机规划模型和适用于不确定参数区间的三阶段鲁棒优化模型。随后，本文结合上述问题与模型的特征，设计了定制化的禁忌搜索算法和粒子群算法分别求解随机模型和鲁棒模型中的大规模问题；并通过一些基于实际问题规模和数据特征的实验，验证了本文所构建的决策模型的有效性和所设计算法的求解效率。本文研究所提出的邮轮废弃物排放决策方法论对当前全球绿色航运事业的推广与发展具有一定应用价值和指导意义。