Heuristic Approaches for Scheduling in Parallel Machine Environments

Efficient and effective scheduling is crucial for ensuring the productivity and competitiveness of production lines, contributing significantly to organizational sustainability. This study addresses the scheduling challenges faced by a UK-based steel reinforcement manufacturer. We propose a heuristic algorithm to tackle a multistage flexible flow shop scheduling problem, where each stage consists of parallel unrelated machines. … Read more

Simplified Copositive and Lagrangian Relaxations for Linearly Constrained Quadratic Optimization Problems in Continuous and Binary Variables

For a quadratic optimization problem (QOP) with linear equality constraints in continuous nonnegative variables and binary variables, we propose three relaxations in simplified forms with a parameter $\lambda$: Lagrangian, completely positive, and copositive relaxations. These relaxations are obtained by reducing the QOP to an equivalent QOP with a single quadratic equality constraint in nonnegative variables, … Read more