A general discrete hub network model that accounts for fixed, capacity, and operating/congestion costs on links and at hubs, with both economies and diseconomies of scale, selects hubs and links, determines their capacities, and assigns O-D flows over paths, while minimizing all system costs. Initially formulated as a mixed-integer non-linear program, the model is transformed into a mixed-integ...

GSM Network Designs usually offers big challenges for achieving an efficient cost while respecting the complex combinatorial technical constraints. This networks have hundred or thousands BTS. They have their traffic grouped in hubs, then in BSC nodes to reach the MSC. Hubs must be elected within the BTS set and BSC nodes have to be geographically allocated in the available sites. Also, the num...

We study random graphs with arbitrary distributions of expected degree and derive expressions for the spectra of their adjacency and modularity matrices. We give a complete prescription for calculating the spectra that is exact in the limit of large network size and large vertex degrees. We also study the effect on the spectra of hubs in the network, vertices of unusually high degree, and show ...

Most studies of protein networks operate on a high level of abstraction, neglecting structural and chemical aspects of each interaction. Here, we characterize interactions by using atomic-resolution information from three-dimensional protein structures. We find that some previously recognized relationships between network topology and genomic features (e.g., hubs tending to be essential protein...

This paper studies the influence of network topology on the speed and reach of new product diffusion. While previous research has focused on comparing network types, this paper explores explicitly the relationship between topology and measurements of diffusion effectiveness. We study simultaneously the effect of three network metrics: the average degree, the relative degree of social hubs (i.e....

The Purdue University Network Computing Hubs of Indiana, or PUNCH(I), is an Internet-based software infrastructure under development that enables students and faculty at all Purdue campuses in the state of Indiana to use and share unique computational resources. It leverages an existing software infrastructure, the Purdue University Network Computing Hubs (PUNCH). This paper explains the need f...

The complexity of the cells can be described and understood by a number of networks such as protein-protein interaction, cytoskeletal, organelle, signalling, gene transcription and metabolic networks. All these networks are highly dynamic producing continuous rearrangements in their links, hubs, network-skeleton and modules. Here we describe the adaptation of cellular networks after various for...