New integer programming models for slab stack shuffling problems

Joint optimization of steel plate shuffling and truck loading sequencing based on deep reinforcement learning

“…In practical operations, magnetic overhead cranes are primarily used for handling steel plates, and the crane typically lifts only one steel plate at a time for safety. ✓ GA Shi and Liu [14] ✓ VLSN Rajabi et al [15] ✓ IP Petering and Hussein [19] ✓ LA-N Boysen and Emde [23] ✓ ✓ IP Boge and Knust [10] ✓ ✓ SA Azab and Morita [24] ✓ IP Galle et al [26] ✓ PBFS Zweers et al [27] ✓ B&B This paper ✓ ✓ AltDRL…”

“…In [14], Shi and Liu developed a very large-scale neighborhood (VLSN) search algorithm to iteratively solve the steel hot rolling scheduling problem considering SSS. Rajabi et al [15] considered two different variants of the SSS problem and proposed a new integer programming (IP) model for each variant. Wu et al [3] introduced a stack-based retrieval method to minimize the unproductive relocation number according to a specific retrieval stack sequence.…”

“…Following the model in [30], the transformations of the stack configuration can be expressed as constraints ( 15)-( 21). In constraint (15), the stack configuration is initialized utilizing the parameter ỹ𝑖𝓁𝑘 , and the configuration status of adjacent intervals and adjacent stages can be updated by constraints ( 16) and (17), respectively. Constraint (18) indicates that a slot can only hold one order.…”

A unifying framework and a mathematical model for the Slab Stack Shuffling Problem

“…Computational experiments on randomly generated instances demonstrated the best performance of the proposed approach compared to constructive and classic local search heuristics. Recently, Rajabi et al (2022) proposed novel integer programming models accounting for two different repositioning policies, i.e., where (i) shuffled slabs are relocated in their original stack after each retrieval or (ii) only when all the retrievals from the same stack are completed. The authors developed ad-hoc algorithms to generate initial feasible solutions, which were used to warm start the solution process (performed using an off-the-shelf solver).…”

“…Despite its importance, the SSSP has received little scholars' attention: indeed, to the best of our knowledge, only a few studies, that we detail in the next section, are found in the literature. Drawing upon the seminal paper by Tang et al (2001), extant contributions focused on the proposal of more refined formulations and solution methods (Tang et al 2002;Singh and Tiwari, 2004;Fernandes et al, 2012;Shi and Liu, 2021;Rajabi et al, 2022) or variants of the problem at hand (Cheng and Tang, 2010;Tang and Ren, 2010;Ren and Tang, 2010).…”