6,442 research outputs found
IMPACT: Investigation of Mobile-user Patterns Across University Campuses using WLAN Trace Analysis
We conduct the most comprehensive study of WLAN traces to date. Measurements
collected from four major university campuses are analyzed with the aim of
developing fundamental understanding of realistic user behavior in wireless
networks. Both individual user and inter-node (group) behaviors are
investigated and two classes of metrics are devised to capture the underlying
structure of such behaviors.
For individual user behavior we observe distinct patterns in which most users
are 'on' for a small fraction of the time, the number of access points visited
is very small and the overall on-line user mobility is quite low. We clearly
identify categories of heavy and light users. In general, users exhibit high
degree of similarity over days and weeks.
For group behavior, we define metrics for encounter patterns and friendship.
Surprisingly, we find that a user, on average, encounters less than 6% of the
network user population within a month, and that encounter and friendship
relations are highly asymmetric. We establish that number of encounters follows
a biPareto distribution, while friendship indexes follow an exponential
distribution. We capture the encounter graph using a small world model, the
characteristics of which reach steady state after only one day.
We hope for our study to have a great impact on realistic modeling of network
usage and mobility patterns in wireless networks.Comment: 16 pages, 31 figure
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Visualizing pain data for wheelchair users: A ubiquitous approach
Copyright @ 2005 Rinton PressWe describe a wireless enabled solution for the vizualisation of pain data. Our approach uses pain drawings to record spatial location and type of pain and enables data collection with appropriate time stamping, thus providing a means for the seldom-recorded (but often attested) time-varying nature of pain, with consequential impact on monitoring the effectiveness of patient treatment regimes. Moreover, since the implementation platform of our solution is that of a Personal Digital Assistant (PDA), data collection takes place ubiquitously, providing back pain sufferers with mobility problems (such as wheelchair users) with a convenient means of logging their pain data and of seamlessly uploading it to a hospital server using WiFi technology. Stakeholder results show that, notwithstanding problems related to PDA data input, our approach is generally perceived to be an easy to use and convenient solution to the challenges of
anywhere/anytime data collection
First experiences with Personal Networks as an enabling platform for service providers
By developing demonstrators and performing small-scale user trials, we found various opportunities and pitfalls for deploying personal networks (PNs) on a commercial basis. The demonstrators were created using as many as possible legacy devices and proven technologies. They deal with applications in the health sector, home services, tourism, and the transportation sector. This paper describes the various architectures and our experiences with the end users and the technology. We conclude that context awareness, service discovery, and content management are very important in PNs and that a personal network provider role is necessary to realize these functions under the assumptions we made. The PNPay Travel demonstrator suggests that PN service platforms provide an opportunity to develop true trans-sector services
Modeling and analyzing variability for mobile information systems
Abstract. Advances in size, power, and ubiquity of computing, sensors, and communication technology made possible the development of mobile or nomadic information systems. Variability of location and system behavior is a central issue in mobile information systems, where behavior of software has to change and re-adapt to the different location settings. This paper concerns modeling and analysis of the complementary relation between software and location variability. We use graphical and formal location modeling techniques, show how to elicit and use location model in conjunction with Tropos goal-oriented framework, and introduce automated analysis on the location-based models.
Location-based software modeling and analysis: Tropos-based approach
Abstract. The continuous growth of interest in mobile applications makes the concept of location essential to design and develop software systems. Location-based software is supposed to be able to monitor the surrounding location and choose accordingly the most appropriate behavior. In this paper, we propose a novel conceptual framework to model and analyze location-based software. We mainly focus on the social facets of locations adopting concepts such as actor, resource, and location-based behavior. Our approach is based on Tropos methodology and allows the analyst to elicit and model software requirements according to the different locations where the software will operate. We propose an extension of Tropos modeling and adapt its process to suit well with the development of location-based software. The proposed framework also includes automated analysis techniques to reason about the relation between location and location-based software.
Seamless mobility with personal servers
We describe the concept and the taxonomy of personal servers, and their implications in seamless mobility. Personal servers could offer electronic services independently of network availability or quality, provide a greater flexibility in the choice of user access device, and support the key concept of continuous user experience. We describe the organization of mobile and remote personal servers, define three relevant communication modes, and discuss means for users to exploit seamless services on the personal server
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Mobile consultant: Evaluation of additional services
As the need for mobility in the medical world increases, newer systems and applications came to light; many of them based on wireless and mobile networks. PDA based systems were presented in the past, capable of videoconferencing and transmitting high quality images between a roaming consultant and a fixed point in the hospital. These systems not only had desirable characteristics but also incorporated additional services that were found of value: paging, Voice over IP calling, Internet, email, intranet, patient record update, etc. This paper presents an engineering and clinical evaluation of those additional services based on both objective and subjective criteria. It concludes that such complementary services can be desirable as they increase personnel mobility, utilize the hospital resources more efficiently while at the same time increase productivity and decrease the cost of hardware and communications
The LAB@FUTURE Project - Moving Towards the Future of E-Learning
This paper presents Lab@Future, an advanced e-learning platform that uses novel Information and Communication Technologies to support and expand laboratory teaching practices. For this purpose, Lab@Future uses real and computer-generated objects that are interfaced using mechatronic systems, augmented reality, mobile technologies and 3D multi user environments. The main aim is to develop and demonstrate technological support for practical experiments in the following focused subjects namely: Fluid Dynamics - Science subject in Germany, Geometry - Mathematics subject in Austria, History and Environmental Awareness – Arts and Humanities subjects in Greece and Slovenia. In order to pedagogically enhance the design and functional aspects of this e-learning technology, we are investigating the dialogical operationalisation of learning theories so as to leverage our understanding of teaching and learning practices in the targeted context of deployment
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