Deteriorating inventory management model: adapting to variable lead time and consumer-driven shortages

Nowadays, businesses work together and create supply chain alliances under a particular framework, such as vendor-managed inventory. The collaboration increases visibility, which reduces costs. It aids in enhancing the environmental performance of the supply chain. Inventory model suggested here helps managers choose the optimum inventory options while considering logistics costs. It elevates the provider to a dominant position, and clients are solely supplied by that vendor. Two models are presented in this research. In the first model, the vendor and customer are expected to make a non-collaborative decision. In the second approach, the merchant and the customer decide. This work proposes an iterative process for determining the best answer, which is then tested using numerical examples demonstrating the presented models' outcomes. The current research proposes a unique evidential theory-based technique for solving an inventory model with stochastic deterioration rates and lead times that appears in a single-vendor multi-buyer inventory system.