Guest Editorial: Theme issue on location and context-aware services

Abstract

Mobile devices, especially smartphones and tablets, are becoming very popular. With the mobile technologies, it is convenient to collect and process data and to provide needed services in real time. Nowadays, people are accustomed to using a smartphone or a tablet to handle the matters in daily life. For example, online payment, personal financial management, social interaction, etc. Besides these well-accepted applications, we believe that services based on location data and context information will play a more important role in the near future. Thus, this theme issue aimed at attracting original and significant research on systems and services that sense, filter, and utilize the location of contextual information on mobile devices. Authors with relevant papers from the AINA-2012 conference (the 26th IEEE International Conference on Advanced Information Networking and Applications) were invited to extend their papers for this theme issue. In addition, an open call for papers was also announced and circulated. At the end of the review process, we accepted seven papers for this theme issue. Each of the papers was peer reviewed by at least two experts in the field. The seven selected papers cover state-of-the-art research issues of location and context-aware services. In the following, we briefly introduce these papers. The first paper titled ‘‘Effects of Population Size for Location-aware Node Placement in WMNs: Evaluation by a Genetic Algorithm Based Approach’’ by Oda et al. uses the genetic algorithm in optimizing the deployment of mesh routers and mesh clients in wireless mesh networks (WMNs). WMNs can serve as an infrastructure for advanced location-aware services. To efficiently support such services and to offer QoS, the placement of mesh router nodes needs to be optimized. Such optimized mesh node distribution can keep the rate of location updates low and support location service managed in the mesh well. The second paper titled ‘‘Hybrid Indoor and Outdoor Location Services for New-Generation Mobile Terminals’’ by Ficco et al. proposes a ubiquitous positioning system of mobile devices in both indoor and outdoor environments. It proposes a hybrid approach that can automatically switch among multiple positioning technologies, while the mobile device is moving. The location services combine signal strength-based fingerprinting techniques for indoor positioning with traditional GPS-based positioning for the outdoor localization. Opportunistic technology switching is performed according to a count-and-threshold mechanism. The third paper titled ‘‘A Connectivity Index for Moving Objects in Indoor Cellular Space’’ by Alamri et al. focuses on indoor positioning of moving objects. The author proposes a new index structure based on the connectivity between the environment cells for moving objects. The index can effectively respond to the spatial indoor queries and enable efficient updates of the location of a moving object in indoor space. The proposed indoor tree performs very well in an empirical study. The fourth paper titled ‘‘A Location-based Personal Task Reminder for Mobile Users’’ by Lin and Hung presents an electronic task reminder based on the calendar in smartphones. In many situations, tasks are only meaningful to be performed at a specific location. This task reminder is triggered by location of the mobile user, not by time as most of other reminder services. This work takes advantage H. Hsu (&) Tamkang University, New Taipei City, Taiwan e-mail: h_hsu@mail.tku.edu.tw