Now showing 1 - 10 of 19
  • Publication
    Diversity & interoperability : wireless technologies in ambient assisted living
    Ambient Assisted Living (AAL) demands the seamless integration of a range of technologies such that the particular needs of the elderly may be met. Given the heterogeneity of the elderly population, in their needs and circumstances amongst others, this is a significant challenge. In essence, it demands that a disparate suite of technologies be deployed, integrated, managed and interacted with in a seamless and intuitive fashion. In this paper, how this heterogeneity may be managed is discussed. In particular, the use of ontologies and middleware are proposed as potential solutions to this heterogeneity problem.
      645
  • Publication
    Timing and radius considerations for maintaining connectivity QoS
    Given the potential scale on which a Wireless Sensor Network (WSN) can be deployed, multi-hop communication will be a pivotal component of the system. When redundant nodes are deployed, which are hibernated opportunistically to conserve energy, it is crucial that sub-graphs of the network are not disconnected by the hibernation of a node. In order to ensure connectivity is preserved for all nodes in the area, a protocol is required that oversees routing integrity is maintained. Since this routing topology must be present at all times, this set represents the minimum number of nodes that must be active at any given time for a functioning network. In this paper, the performance of such a protocol is evaluated, in terms of message delivery and node lifetime for various timing and radius parameters. The selection of these, control the potential energy conserved by the nodes through the hibernation process, which can increase operational longevity. In addition, the radius governs the networks resilience to expired nodes, while timing parameters manage the responsiveness of the topology to failed and exhausted sensors. In this paper, we demonstrate the trade-offs that exist when selecting specific values for these variables as well as the impact these have on a number of Quality of Service (QoS) metrics for WSN performance, namely longevity and message delivery.
      525
  • Publication
    Realising an Agent-oriented middleware for Heterogeneous Sensor Networks
    Classic computing systems are characterised by heterogeneity, with its inherent advantages and disadvantages. This raises a number of difficulties for software engineers. The vision offered by a mix-and-match approach is an attractive one, though its practical realisation comes at a cost, as the process of integration is rarely smooth. This scenario will be repeated as Wireless Sensor Networks are increasingly incorporated into mainstream computing. One potential paradigm for managing this heterogeneity is that of intelligent agents. This paper considers the viability and potential of lightweight agents as a paradigm for harnessing the potential of heterogeneous wireless sensor networks.
    Scopus© Citations 3  1132
  • Publication
    Agent-based coordination for the sensor web
    The approach described advocates the use of a multi-agent system, and specifically the use of multi-agent distributed constraint optimisation algorithms. Developing software for low powered sensing devices introduces several problems to be addressed; the most obvious being the limited computational resources available. In this paper we discuss an implementation of ADOPT, a pre-existing algorithm for distributed constraint optimisation, and describe how it has been integrated with a reflective agent platform developed for resource constrained devices, namely Agent Factory Micro Edition (AFME). The usefulness of this work is illustrated through the canonical multi-agent coordination problem, namely graph colouring.
      16038Scopus© Citations 2
  • Publication
    Air quality monitoring for pervasive health
    Two monitoring projects relate to this issue's theme, "Hostile Environments": "Landslide Monitoring in the Emilia Romagna Apennines" and "Air Quality Monitoring for Pervasive Health." In addition, "Task-Driven Framework for Pervasive Computing" reports on TaskOS, a project to develop task-driven recommendation systems for pervasive computing environments.
      341Scopus© Citations 1
  • Publication
    A mobile gateway for remote interaction with wireless sensor networks
    Wireless Sensor Networks (WSNs) almost invariably support a centralised network management model. Though the data gathering function is conducted remotely, such data is usually routed via data sinks to central servers for processing, storage, visualisation and interpretation. However, the issue of supporting remote access to WSNs and individual sensor nodes whilst in their physical environment has not been viewed as a priority. It is envisaged that this situation will change as WSNs proliferate in a range of domains, and the potential for supporting innovative revenue-generating services manifest themselves. As a step towards realising such access, a mobile gateway has been designed and implemented. This gateway supports Zigbee as this is the predominant protocol supported by WSNs. Furthermore, it also supports Bluetooth, thereby facilitating interaction with conventional mobile devices. The gateway is programmable according to the needs of arbitrary services and applications.
    Scopus© Citations 23  1563
  • Publication
    Sensor Web Interaction
    Ubiquitous sensing fuses the concepts of intelligent systems with ubiquitous computing in the development of novel sensor web applications, whereby the interaction of multiple disparate autonomous artefacts is a key requirement. In this paper, we present SIXTH, which is a middleware infrastructure for Ubiquitous Sensing that facilitates, and supports, the development and deployment of Sensor Web applications. SIXTH has been designed to be extensible, with provisions for user definable data retention policies, custom sensor data representations, and custom sensor node representations, whilst still providing a rich set of default behaviours. Within SIXTH, support is provided for the development and interaction of applications that incorporate both physical and cyber (virtual server side) sensors. With a view to supporting intelligent, in network, interaction policies, whereby sensor nodes must negotiate and coordinate their behaviour, the system has been designed to operate in conjunction with Agent Factory Micro Edition (AFME). AFME is a minimised footprint intelligent agent platform designed for resource constrained devices. It is based on the standard Agent Factory platform, which was developed for desktop machines, and is representative of a class of agent systems, which are referred to as Agent Oriented Programming frameworks. The paper discusses a ubiquitous mapping application that was developed using the middleware.
    Scopus© Citations 28  1092
  • Publication
    Fuzzy decision making through energy-aware and utility agents within wireless sensor networks
    Multi-agent systems (MAS) through their intrinsically distributed nature offer a promising software modelling and implementation framework for wireless sensor network (WSN) applications. WSNs are characterised by limited resources from a computational and energy perspective; in addition, the integrity of the WSN coverage area may be compromised over the duration of the network's operational lifetime, as environmental effects amongst others take their toll. Thus a significant problem arises--how can an agent construct an accurate model of the prevailing situation in order that it can make effective decisions about future courses of action within these constraints? In this paper, one popular agent architecture, the BDI architecture, is examined from this perspective. In particular, the fundamental issue of belief generation within WSN constraints using classical reasoning augmented with a fuzzy component in a hybrid fashion is explored in terms of energy-awareness and utility.
    Scopus© Citations 11  2001
  • Publication
    Simulating interaction with wireless sensor networks
    Wireless Sensor Networks(WSNs) are primarily regarded as data gathering entities that route data to a central server for subsequent processing. However, as WSN technologies mature and their prevalence increases, it is envisaged that a range of diverse and innovative services for mobile subscribers will be launched, of which some may require remote access and interaction with individual WSNs. Such an eventuality will give rise to additional constraints in the WSN planning and deployment processes, and raise particular challenges in the practical engineering of mobile applications and services. In this paper, a simulation tool is described. This tool enables software engineers rapidly model WSN deployments, and in this way, explore how interactions between mobile users and WSNs may occur.
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  • Publication
    Managing diversity in practical ambient assisted living ecosystems
    Though the motivation for developing ambient assisted living (AAL) systems is incontestable, significant challenges exist in realizing the ambience that is essential to the success of such systems. By definition, an AAL system must be omnipresent, tracking occupant activities in the home and identifying those situations where assistance is needed or would be welcomed. Embedded sensors offer an attractive mechanism for realizing ambience as their form factor and harnessing of wireless technologies aid in their seamless integration into pre-existing environments. However, the heterogeneity of the end-user population, their disparate needs and the differing environments in which they inhabit, all pose particular problems regarding sensor integration and management.
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