Background The Lablite project captured information on access to antiretroviral therapy (ART) at larger health facilities ('hubs') and lower-level health facilities ('spokes') in Phalombe district, Malawi and in Kalungu district, Uganda. Methods We conducted a cross-sectional survey among patients who had transferred to a spoke after treatment initiation (Malawi, n=54; Uganda, n=33), patients...

Using covering problems (CoP) combined with binary search is a well-known and successful solution approach for solving continuous center problems. In this paper, we show that this is also true for center hub location problems in networks. We introduce and compare various formulations for hub covering problems (HCoP) and analyse the feasibility polyhedron of the most promising one. Computational...

Through observations from real life hub networks, we introduce the multimodal hub location and hub network design problem. We approach the hub location problem from a network design perspective. In hub network design problem, we jointly consider transportation costs and travel times, which are studied separately in most hub location problems presented in the literature. We allow different trans...

Abstract One of the basic assumptions in hub covering problems is considering the covering radius as an exogenous parameter which cannot be controlled by the decision maker. Practically and in many real world cases with a negligible increase in costs, to increase the covering radii, it is possible to save the costs of establishing additional hub nodes. Change in problem parameters during the pl...

It has been claimed that proteins with more interacting partners (hubs) are structurally more disordered and have a slow evolutionary rate. Here, in this paper we analyzed the evolutionary rate and structural disorderness of human hub and non-hub proteins present/absent in protein complexes. We observed that both non-hub and hub proteins present in protein complexes, are characterized by high s...

centralizing and using proper transportation facilities cut down costs and traffic. hub facilities concentrate on flows to cause economic advantage of scale and multimodal transportation helps use the advantage of another transporter. a distinctive feature of this paper is proposing a new mathematical formulation for a three-stage p-hub location routing problem with simultaneous pick-ups and de...

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...

this paper presents the fatigue life behavior of hub using random vibration based on road roughness. the main objectives of this study are to predict the fatigue life and to identify the critical location for evaluating fatigue damage. asphalt road surface profiles obtained in favorable circumstances by topography cameras and in according road classification iso 2631-1estimate road roughness su...