The Two-Echelon Vehicle Routing Problem (2E-VRP) is an extension of the classical VRP where the delivery from a single depot to customers is managed by routing and consolidating the freight through intermediate depots called satellites. We presented several meta-heuristics based on separating the first and second level routing problems and solving iteratively the two resulting routing subproble...

In this paper we analyze stock allocation policies in general N-echelon distribution systems, where it is allowed to hold stock at all levels in the network. The goal is to achieve differentiated target customer service levels (fill rates). Various allocation rules and accompanying numerical methods that have already been developed for smaller networks are extended and compared in an extensive ...

Given the emergence of two-echelon distribution systems in several practical contexts, this paper tackles, at strategic level, a network design problem under uncertainty. This is defined as stochastic multi-period capacitated location-routing (2E-SM-CLRP). It considers partitioned into two echelons: each echelon involves specific location-assignment-transportation schema that must cope with fut...

In allusion to such problems as low accuracy and long convergence time in traditional two-echelon vehicle routing optimization algorithm, a Memetic algorithm (QDEMA) based on Q learning theory and differential evolution is proposed in this article to solve above problems. Firstly, it is necessary to research the two-echelon vehicle routing optimization problem and adopt the optimal segmentation...

The minimum concave cost network flow problem (MCCNFP) is NP-hard, but efficient polynomial-time algorithms exist for some special cases such as the uncapacitated lot-sizing problem and many of its variants. We study the MCCNFP over a grid network with a general nonnegative separable concave cost function. We show that this problem is polynomially solvable when all sources are in the first eche...

In this paper, a new multi-objective integer non-linear programming model is developed for designing citrus three-echelon supply chain network. Short harvest period, product specifications, high perished rate, and special storing and distributing conditions make the modeling of citrus supply chain more complicated than other ones. The proposed model aims to minimize network costs includin...