Abstract

With 212 locations serving a geographical area three times the size of the state of Texas, our international client has been experiencing unexpected failures in his portfolio of thousands of refrigeration units, resulting in an associated loss of $1.4 million. These losses have been attributed to lapses in food quality caused by improper refrigeration, and the adopted reactive maintenance strategy of the refrigeration units. To assist our client in complying with the cold-chain regulations of food safety and mitigate such losses, the agent-based simulation was used to model and assess the viability of two distinct massively populated Internet of Things (IoT) alternatives. The first (alternative A) involves monitoring the availability of each of the refrigeration units and signaling for the initiation of repair processes and food removal from failed units when the cooling temperature differs from a specified threshold and a more sophisticated and expensive alternative B that involves the adoption of the added capability of a condition-based predictive maintenance strategy to reduce unplanned downtime and mitigate or eliminate the causes of failure. Using historical data, a simulation of the current operations was first modeled, validated, and then augmented with capabilities to address the operational characteristics of the proposed IoT implementations. Results of financial analysis results including the probabilistic risk analyses, that account for the variations and the probability distributions of the assumption parameters, showed alternative A to be superior, with a mean net present value (NPV) of $416,703, and a modified IRR of about 18.77% exceeding the project cost of capital of 12.80% with complete certainty. The client was also advised that a 30% reduction in the acquisition cost would make investment B as viable as investment A.

摘要

我们的国际客户有212个地点，服务的地理面积是德克萨斯州的三倍，在其成千上万个制冷单元的产品组合中遇到了意外故障，造成了140万美元的相关损失。这些损失归因于制冷不当导致的食品质量下降，以及制冷机组采用的被动维护策略。为了帮助我们的客户遵守食品安全的冷链法规并减轻此类损失，基于代理的模拟被用来建模和评估两种不同的人口众多的物联网（IoT）替代方案的可行性。第一个（替代方案A）涉及监视每个制冷单元的可用性，并在冷却温度不同于指定阈值时发出信号以启动维修过程和从故障单元中取出食物，以及涉及更复杂和昂贵的替代方案B。采用基于状态的预测性维护策略的附加功能，以减少计划外的停机时间并减轻或消除故障原因。使用历史数据，首先对当前操作的仿真进行建模，验证，然后通过增强功能来解决建议的物联网实施的操作特征。财务分析结果包括概率风险分析，考虑假设参数的变化和概率分布的结果表明，备选方案A更好，平均净现值（NPV）为416,703美元，修正的内部收益率约为18.77％，超过项目资本成本的12.80％完全确定 还告知客户，购置成本降低30％将使投资B与投资A一样可行。