The ordered median function unifies and generalizes most common objective functions used in location theory. It is based on the ordered weighted averaging (OWA) operator with the preference weights allocated to the ordered distances. Demand weights are used in location problems to express the client demand for a service thus defining the location decision output as distances distributed according to measures defined by the demand weights. Typical ordered median model allows weighting of several clients only by straightforward rescaling of the distance values. However, the OWA aggregation of distances enables us to introduce demand weights by rescaling accordingly clients measure within the distribution of distances. It is equivalent to the so-called weighted OWA (WOWA) aggregation of distances covering as special cases both the weighted median solution concept defined with the demand weights (in the case of equal all the preference weights), as well as the ordered median solution concept defined with the preference weights (in the case of equal all the demand weights). This paper studies basic models and properties of the weighted ordered median problem (WOMP) taking into account the demand weights following the WOWA aggregation rules. Linear programming formulations were introduced for optimization of the WOWA objective with monotonic preference weights thus representing the equitable preferences in the WOMP. We show MILP models for general WOWA optimization. B Włodzimierz Ogryczak

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This paper presents the Content Aware Network designed as one of the Parallel Internets developed on Virtual Infrastructure. The CAN is a post-IP network designed to facilitate access to multimedia content in large scale environment. We introduce the proposed CAN network architecture and discuss mechanisms and algorithms required to assure ubiquitous content access and efficient content delivery. In particular, we propose new content naming and resolution schemes, an effective content source selection algorithm, which optimize resource utilization and the flexible content delivery method. Moreover, we present developed prototype and numerical results illustrating effectiveness of proposed CAN delivery method.