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....

The protein-protein interaction (PPI) networks are dynamically organized as modules, and are typically described by hub dichotomy: 'party' hubs act as intramodule hubs and are coexpressed with their partners, yet 'date' hubs act as coordinators among modules and are incoherently expressed with their partners. However, there remains skepticism about the existence of hub dichotomy. Since differen...

We consider two problems that arise in designing two-level star networks taking into account service quality considerations. Given a set of nodes with pairwise traffic demand and a central hub, we select p hubs and connect them to the central hub with direct links and then we connect each nonhub node to a hub. This results in a star/star network. In the first problem, called the Star p-hub Cent...

This paper studies a closed queueing network containing a hub (a state dependent queueing system with service depending on the number of units residing here) and k satellite stations, which are GI/M/1 queueing systems. The number of units in the system, N , is assumed to be large. After service completion in the hub, a unit visits a satellite station j, 1 ≤ j ≤ k, with probability pj , and, aft...

Human clear cell renal cell carcinoma (ccRCC) is one of the most common types of malignant adult kidney tumors. We constructed a weighted gene co-expression network to identify gene modules associated with clinical features of ccRCC (n = 97). Six hub genes (CCNB2, CDC20, CEP55, KIF20A, TOP2A and UBE2C) were identified in both co-expression and protein-protein interaction (PPI) networks, which w...

Transportation networks frequently employ hub-and-spoke network architectures to route flows between many origin and destination pairs. In this paper, we deal with a problem, called the single allocation hub-and-spoke network design problem. In the single allocation hub-andspoke network design problem, the goal is to allocate each non-hub node to exactly one of given hub nodes so as to minimize...

Connectivity in the developing hippocampus displays a functional organization particularly effective in supporting network synchronization, as it includes superconnected hub neurons. We have previously shown that hub network function is supported by a subpopulation of GABA neurons. However, it is unclear whether hub cells are only transiently present or later develop into distinctive subclasses...

Hubs are special centers that used for switching, transferring and handling freight or passengers in transportation systems. The hub location problem deals with locating hub facilities and allocating demand nodes to hubs in order to route the traffic between origin–destination pairs. Aiming at minimizing the total costs, maximizing utilization of transporters, maximizing the service level, etc....

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...

Let π1 : K H , π2 : H G and π2π1 : K G be three finite regular coverings of graphs, and let σ be a representation of the covering transformation group of π1. We show that the L-function of G associated to the representation of the covering transformation group of π2π1 induced from σ is equal to that of H associated to σ by means of ordinary voltage assignments. © 2003 Elsevier Science Ltd. All ...