This paper deals with a hub location-routing problem (HLRP) which integrates the hub location problem (HLP) and the multi-hub vehicle routing problem (MH-VRP) in parcel delivery service. The HLRP is very difficult to be solved since it is composed of two NP-hard problems, the HLP and the MH-VRP. To solve these problems simultaneously we present a novel solution framework which divides the probl...

We consider the problem of recovering the graph structure of a “hub-networked” Ising model given i.i.d. samples, under high-dimensional settings, where number of nodes p could be potentially larger than the number of samples n. By a “hub-networked” graph, we mean a graph with a few “hub nodes” with very large degrees. State of the art estimators for Ising models have a sample complexity that sc...

This article considers the problem of designing a twolevel network where the upper level consists of a backbone ring network connecting the so-called hub nodes, and the lower level is formed by access ring networks that connect the non-hub nodes to the hub nodes. There is a fixed cost for each type of link, and a facility opening cost associated to each hub. The number of nodes in each access r...

We study the hub location and routing problem where we jointly decide on the location of hubs, the allocation of nodes to hubs, and the routing among the nodes allocated to the same hubs, with the aim of minimizing the total transportation cost. Each hub has one vehicle that visits all the nodes assigned to it on a cycle. We propose a mixed integer programming formulation for this problem and s...

Considering the hub airports are traffic transfer points, the congestion is easily happened. The cost caused by congestion will rise significantly. The hub-and-spoke airline network optimization model with congestion cost is designed. In the actual operations of airlines, such problem is difficult to be solved by using the classical optimization methods. This paper presents a Particle Swarm Opt...