In automated storage and retrieval systems (AS/RS), the usage of intelligent algorithms can lead to a reduction in the makespan required to complete a series of input/output operations. This paper presents a simulation-optimisation algorithm which aims at minimising the makespan in a realistic...

This paper presents a travel time model for multi-deep AS/RS, which determines the average travel times during a single command storage or retrieval and a dual command cycle. The model can determine the relocation probability, the number of expected relocations and the travel times in storage...

The paper presents analysis of the storage systems used by social network sites. Namely, the social networks are one of the main driving forces behind the NoSQL database development. Facebook and Twitter were, together with other the Big Data players like Google and Amazon, first faced with the...

Wave-based release policies are prevalent in warehouses with an automated sorter, and take different forms depending on how much waves overlap and whether the sorter is split for operating purposes. Waveless release is emerging as an alternative policy adopted by an increasing number of firms....

The stowage decision determines how arriving products are distributed in a storage system or warehouse. In particular we consider the zone-stowage decision for large warehouses that are organized into distinct storage zones. An example would be a multi-floor warehouse where each floor is a...

Our research focuses on the storage decision in a semi-automated storage system, where the inventory is stored on mobile storage pods. In a typical system, each storage pod carries a mixture of items, and the inventory of each item is spread over multiple storage pods. These pods are transported...

Autonomous vehicle-based storage and retrieval systems are commonly used in e-commerce fulfillment as they allow a high and flexible throughput capacity. In these systems, roaming robots transport loads between a storage location and a workstation. Two main variants exist: Horizontal, where the...