Supply chain resilience to sudden and simultaneous lead-time and demand disturbances

This paper takes up the study of the resilience of a supply chain when subjected to sudden increases in both demand as well as replenishment lead times. The definition of resilience leads quite naturally to the use of dynamic analysis; and hence we examine the resilience of the chain through the study of the dynamic behaviour of the distribution warehouse at its downstream end, catering to its demand off-take and operating under a 'responsiveness' strategy. We derive the dynamic behaviour of the warehouse system under different dynamic replenishment control schemes and attempt to synthesise a modified dynamic control scheme to enhance its resilience and performance under such conditions. A notable feature of these dynamic controls is that they can be made pro-active as is shown in the paper. We then compare the system response with those of parallel systems closely related to the one studied in this paper and highlight the increased difficulty in controlling this system compared to the others.