Hub networks have always been acriticalissue in locating health facilities. Recently, a study has been investigated by Cocking et al. (2006)in Nouna health district in Burkina Faso, Africa, with a population of approximately 275,000 people living in 290 villages served by 23 health facilities. The travel times of the population to health services become extremely high during the rainy season, s...

Abstract. We consider a single allocation hub-and-spoke network design problem which allocates each non-hub node to exactly one of given hub nodes so as to minimize the total transportation cost. This paper deals with a case in which the hubs are located in a cycle, which is called a cycle-star hub network design problem. The problem is essentially equivalent to a cycle-metric labeling problem....

Due to the increase of users the efficient usage of spectrum plays an important role in digital terrestrial television networks. In digital video broadcasting, local and global content are transmitted by single frequency network and multifrequency network respectively. Multifrequency network support transmission of global content and it consumes large spectrum. Similarly local content are well ...

Hubs are facilities used to treat and dispatch resources in a transportation network. The main idea of Hub Location Problems (HLP) is to locate a number of hubs in a network and route resources from origins to destinations such that the total cost of attending all demands is minimized. In this study, we investigate a particular HLP, called the Tree of Hubs Location Problem in which hubs are con...

This paper discusses the fixed-hub single allocation problem. In the model hubs are fixed and fully connected; and each terminal node is connected to a single hub which routes all its traffic. The goal is to minimize the cost of routing the traffic in the network. This paper presents linear programming-based algorithms that deliver both high quality solutions and a theoretical worst case bound....

In the literature, hub-networks have often been modeled such as only one mode is considered for all transportation. Also, consolidated demand flows are assumed to be transferred directly between each origin-destination hub pairs. The previous assumptions impose restrictions on practical applications of hub-networks. fact, various transport modes usually retained freight transport, and intermoda...

We study hierarchical hub labelings for computing shortest paths. Our new theoretical insights into the structure of hierarchical labels lead to faster preprocessing algorithms, making the labeling approach practical for a wider class of graphs. We also find smaller labels for road networks, improving the query speed.

This paper discusses the fixed-hub single allocation problem. In the model hubs are fixed and fully connected; and each terminal node is connected to a single hub which routes all its traffic. The goal is to minimize the cost of routing the traffic in the network. This paper presents linear programming-based algorithms that deliver both high quality solutions and a theoretical worst case bound....

This research is motivated by the extraordinary increase in the use of intermodal shipments in recent years for both domestic and global movement of freight. Three mathematical models, which explore the dynamics of intermodal hub-and-spoke networks, are presented. These models use transportation costs, fixed location costs, modal connectivity costs, modal transit times and service time requirem...

Innovation networks constitute a valid structure within which to foster members’ abilities to interact and cooperate, in order to reduce environmental uncertainty and face the challenges that derive from economic change. Network members take advantage of their participation in the system by creating and extracting value when performing certain deliberate and purposeful activities. Traditionally...