There exist various service systems that have hierarchical structure. In hierarchical service networks, facilities at different levels provide different types of services. For example, in health care systems, general centers provide low-level services such as primary health care services, while the specialized hospitals provide high-level services. Because of demand congestion in service networ...

resource allocation techniques have recently appeared as a widely recognized feature in lte networks. most of existing approaches in resource allocation focus on maximizing network’s utility functions. the great potential of utility function in improving resource allocation and enhancing fairness and mean opinion score (mos) indexes has attracted large efforts over the last few years. in this p...

DISCLAIMER This document describes work undertaken as part of a programme of study at the Faculty of Geo-Information Science and Earth Observation of the University of Twente. All views and opinions expressed therein remain the sole responsibility of the author, and do not necessarily represent those of the Faculty. i ABSTRACT Location allocation is a combinatorial optimization problem. Traditi...

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In this paper, we develop a capacitated location-covering model considering interval values for demand and service parameters. We also consider flexibility on distance standard for covering demand nodes by the servers. We use the satisfaction degree to represent the constraint of service capacity. The proposed model belongs to the class of mixed integer programming models. Our model can be redu...

Article history: Received 1 September 2013 Received in revised form 6 May 2014 Accepted 7 May 2014 Available online 20 May 2014

A large number of heuristic search algorithms are available for function optimization. Each of these heuristics, e.g., simulated annealing, genetic algorithms, tabu search, etc., has been shown to be effective at finding good solutions efficiently. However, little work has been directed at determining what are the important problem characteristics for which one algorithm is more efficient than ...