George Roussos

Fast track article: Looking ahead in pervasive computing: Challenges and opportunities in the era of cyber-physical convergence

The physical environment is becoming more and more saturated with computing and communication entities that interact among themselves, as well as with users: virtually everything will be enabled to source information and respond to appropriate stimuli. In this technology-rich scenario, real-world components interact with cyberspace via sensing, computing and communication elements, thus driving towards what is called the Cyber-Physical World (CPW) convergence. Information flows from the physical to the cyber world, and vice-versa, adapting the converged world to human behavior and social dynamics. Indeed humans are at the center of this converged world since information about the context in which they operate is the key element to adapt the CPW applications and services. Alongside, a new wave of (human) social networks and structures are emerging as important drivers for the development of novel communication and computing paradigms. In this article we present some of the research issues, challenges and opportunities in the convergence between the cyber and physical worlds. This article is not a comprehensive survey of all aspects of the CPW convergence. Instead, it presents some exciting research challenges and opportunities identified by members of the journals editorial board with a goal to stimulate new research activities in the emerging areas of CPW convergence.

Developing consumer-friendly pervasive retail systems

Few researchers have explored consumer reactions to pervasive retail systems. The prototype implementation and study results discussed here have important implications for system developments.

rfid in pervasive computing: State-of-the-art and outlook

rfid has already found its way into a variety of large scale applications and arguably it is already one of the most successful technologies in the history of computing. Beyond doubt, rfid is an effective automatic identification technology for a variety of objects including natural, manufactured and handmade artifacts; humans and other species; locations; and increasingly media content and mobile services. In this survey we consider developments towards establishing rfid as the cost-effective technical solution for the development of open, shared, universal pervasive computing infrastructures and look ahead to its future. In particular, we discuss the ingredients of current large scale applications; the role of network services to provide complete systems; privacy and security implications; and how rfid is helping prototype emerging pervasive computing applications. We conclude by identifying common trends in the new applications of rfid and ask questions related to sustainable universal deployment of this technology.

Mobile Identity Management: An Enacted View

The growth of mobile business requires the ability to provide context-aware services when and where needed, the development of trust relationships between trading partners, and an ever-expanding capability to reconfigure value chains. These issues are becoming more prominent with the emergence of converged architectures for next-generation public networks. The integration of the Internet, traditional telephony networks, and consumer electronics brings mobile business to the forefront. In this context, mobile identity management can play a central role in addressing usability and trust issues in mobile business. For this reason, it is being established as a core service for next-generation mobile telecommunications infrastructures. Mobile identity management is used to identify, acquire, access, and pay for services that follow the user from device to device, location to location, and context to context, and thus it is the network component that holds together novel services on novel networks using innovative business models. In contrast to previous-generation mobile business infrastructures, this represents a pivotal shift in focus from identification to identity. The present paper advocates that this shift calls for an enacted view of technology, since the level of involvement of human qualities is unprecedented when discussing identity. It introduces a view of identit y in mobile business based on three principles and finds that this approach is useful in explaining some recent research findings in ubiquitous retailing. Widening the discipline boundaries for future research on identity in mobile business will be essential for the development of effective mobile service provision systems.

Consumer perceptions of privacy, security and trust in ubiquitous commerce

Commerce is a rapidly emerging application area of ubiquitous computing. In this paper, we discuss the market forces that make the deployment of ubiquitous commerce infrastructures a priority for grocery retailing. We then proceed to report on a study on consumer perceptions of MyGrocer, a recently developed ubiquitous commerce system. The emphasis of the discussion is on aspects of security, privacy protection and the development of trust; we report on the findings of this study. We adopt the enacted view of technology adoption to interpret some of our findings based on three principles for the development of trust. We expect that this interpretation can help to guide the development of appropriate strategies for the successful deployment of ubiquitous commerce systems.

A case study in pervasive retail

In this paper we discuss the rationale for the development of MyGrocer, a second-generation pervasive retail system, as well as its implications for the fast moving consumer goods (FMCG) sector. We will only touch upon the technology infrastructure and the required technical developments since these have been discussed extensively elsewhere. The focus here is on the one hand, on the analysis of the business forces that dictate the development of pervasive retail and on the other, the implications and the opportunities for innovative business models offered by the dis-intermediation effect of pervasive retail on the supply chain of FMCG. The MyGrocer system has undergone two phases of field-testing and is expected to be fully operational by the end of this year. The development of the MyGrocer architecture is a collaborative effort between industry and academia within Europe.

Ubiquitous computing in the real world: lessons learnt from large scale RFID deployments

Ubiquitous computing technologies are slowly finding their way into commercial information systems, which are often constructed at considerably larger scale compared to what is possible in research demonstrators. Furthermore, lengthy and costly preparation or upgrade of existing infrastructures, training of employees and users in the new ways of working, controlled introduction of new functionality, features and services to manage risk, unexpected behaviors due to the wider variety of possible real-world situations, incremental approach to systems development so as to better identify successful aspects, regard for the economics of systems as a core requirement, and selection of open or closed systems are all issues that are mostly outside the scope of current ubiquitous computing research but play a critical role in industrial deployments. In this paper we review two case studies of fully operational Radio Frequency Identification-based systems: the Oyster card ticketing system used at the London Underground in the UK, and retail applications deployed at the Mitsukoshi departmental stores in Tokyo, Japan. We examine each case in terms of technologies, user interactions, and their business and organizational context and make several observations in each case. We conclude by drawing general lessons related to ubiquitous computing in the real world and identify challenges for future ubiquitous computing research.

Brief encounters: Sensing, modeling and visualizing urban mobility and copresence networks

Moving human-computer interaction off the desktop and into our cities requires new approaches to understanding people and technologies in the built environment. We approach the city as a system, with human, physical and digital components and behaviours. In creating effective and usable urban pervasive computing systems, we need to take into account the patterns of movement and encounter amongst people, locations, and mobile and fixed devices in the city. Advances in mobile and wireless communications have enabled us to detect and record the presence and movement of devices through cities. This article makes a number of methodological and empirical contributions. We present a toolkit of algorithms and visualization techniques that we have developed to model and make sense of spatial and temporal patterns of mobility, presence, and encounter. Applying this toolkit, we provide an analysis of urban Bluetooth data based on a longitudinal dataset containing millions of records associated with more than 70000 unique devices in the city of Bath, UK. Through a novel application of established complex network analysis techniques, we demonstrate a significant finding on the relationship between temporal factors and network structure. Finally, we suggest how our understanding and exploitation of these data may begin to inform the design and use of urban pervasive systems.Many complex human and natural phenomena can usefully be represented as networks describing the relationships between individuals 1,2,3,4 . While these relationships are typically intermittent, previous research has used network representations that aggregate the relationships at discrete intervals 5 . However, such an aggregation discards important temporal information, thus inhibiting our understanding of the network’s dynamic behaviour and evolution. We have recorded patterns of human urban encounter using Bluetooth technology (Figure 1) thus retaining the temporal properties of this network. Here we show how this temporal information influences the structural properties of the network. We show that the temporal properties of human urban encounter are scale-free, leading to an overwhelming proportion of brief encounters between individuals. While previous research has shown preferential attachment to result in scale-free connectivity in aggregated network data 11 , we found that scale-free connectivity results from the temporal properties of the network. In addition, we show that brief encounters act as weak social ties 6,7 in the diffusion of non-expiring information, yet persistent encounters provide the means for sustaining timeexpiring information through a network.

Escalation: complex event detection in wireless sensor networks

We present a new approach for the detection of complex events in Wireless Sensor Networks. Complex events are sets of data points that correspond to interesting or unusual patterns in the underlying phenomenon that the network monitors. Our approach is inspired from time-series data mining techniques and transforms a stream of real-valued sensor readings into a symbolic representation. Complex event detection is then performed using distance metrics, allowing us to detect events that are difficult or even impossible to describe using traditional declarative SQL-like languages and thresholds. We have tested our approach with four distinct data sets and the experimental results were encouraging in all cases. We have implemented our approach for the TinyOS and Contiki Operating Systems, for the Sky mote platform.

Towards a framework for investigating tangible environments for learning

External representations have been shown to play a key role in mediating cognition. Tangible environments offer the opportunity for novel representational formats and combinations, potentially increasing representational power for supporting learning. However, we currently know little about the specific learning benefits of tangible environments, and have no established framework within which to analyse the ways that external representations work in tangible environments to support learning. Taking external representation as the central focus, this paper proposes a framework for investigating the effect of tangible technologies on interaction and cognition. Key artefact-action-representation relationships are identified, and classified to form a structure for investigating the differential cognitive effects of these features. An example scenario from our current research is presented to illustrate how the framework can be used as a method for investigating the effectiveness of differential designs for supporting science learning.