We consider a two-echelon location-distribution problem arising from an actual application in fast delivery service. This problem belongs to the class of adaptive logistics problems, as the locations of the facilities (typically, parking spaces) are revised on a daily basis according to demand variations. We present and compare two formulations for this problem: an arc-based model and a path-ba...

Many optimization problems including the network design problem of finding the bounded diameter minimum spanning tree are computationally intractable. Therefore, a practical approach for solving such problems is to employ heuristic algorithms that can find solution close to the optimal one within a reasonable amount of time. Neighborhood search algorithms are a wide class of algorithms where at...

This research introduces a new variant of the two-echelon vehicle routing problem (2EVRP) called with transshipment nodes and occasional drivers (2EVRP-TN-OD). In addition to city freighters in second-echelon network, set (ODs) is available serve customers. ODs are basis crowd-shipping system which crowds planned trips willing take detours deliver packages exchange for some compensation. To cus...

The inventory slack routing problem is a specialized vehicle routing problem that focuses on delivering waves of inventory to sites in a timely and even manner. It is difficult to find an optimal solution to this problem, thus heuristic and search techniques are necessary. ...

We provide two different neighborhood construction techniques for creating exponentially large neighborhoods that are searchable in polynomial time using dynamic programming. We illustrate both of these approaches on very large scale neighborhood search techniques for the traveling salesman problem. Our approaches unify previously known results and offer schemas for generating additional expone...

The Minimum Gap Graph Partitioning Problem (MGGPP) consists in partitioning a vertex-weighted undirected graph into given number of connected subgraphs with the minimum difference between largest and smallest weight each subgraph. We propose two-level Tabu Search algorithm an Adaptive Large Neighborhood to solve MGGPP reasonable time on instances up about 23 000 vertices. quality heuristic solu...

The Weibull distribution is widely employed in several areas of engineering because it is an extremely flexible distribution with different shapes. Moreover, it can include characteristics of several other distributions. However, successful usage of Weibull distribution depends on estimation accuracy for three parameters of scale, shape and location. This issue shifts the attentions to the requ...

We propose several new hybrid heuristics for the differential dispersion problem, the best of which consists of a GRASP with sampled greedy construction with variable neighborhood search for local improvement. The heuristic maintains an elite set of high-quality solutions throughout the search. After a fixed number of GRASP iterations, exterior path relinking is applied between all pairs of eli...

We propose several new hybrid heuristics for the differential dispersion problem are proposed, the best of which consists of a GRASP with sampled greedy construction with variable neighborhood search for local improvement. The heuristic maintains an elite set of high-quality solutions throughout the search. After a fixed number of GRASP iterations, exterior path relinking is applied between all...

We provide two different neighborhood construction techniques for creating exponentially large neighborhoods that are searchable in polynomial time using dynamic programming. We illustrate both of these approaches on very large scale neighborhood search techniques for the traveling salesman problem. Our approaches are intended both to unify previously known results as well as to offer schemas f...